1. Quality not Quantity: This to me is the Golden Rule of Twitter. Put every tweet through this filter: “Would my followers really care about this information?” IMHO, the key to a strong and loyal Twitter following is the ability to make sure that almost every tweet you send out is useful to at least a majority of your audience. If your Twitter presence is too noisy/verbose, you may get noticed initially, but you will not get followed and will lose the opportunity to truly connect with your audience over the long term.

   The Quality not Quantity mantra also applies to the number of followers you have and also to the number of people you are following. Accumulating followers by doing silly/underhanded promo tricks (“Follow me to win an iPad” for instance) is not only disgusting, but also quite useless. When someone follows you, you want them to be following you for the right reasons — because they’re truly interested in your company, or your product, or what you have to say. Only those people will be passionate/vocal about your product and that will result in a snowball effect.

   Likewise, if you’re following thousands or tens of thousands of users, then people know that you’re not *really* following them. Bottom line: you have to be discerning about what what you tweet, who follows you and who you follow. Quality, not quantity.

2. Limit Shameless Self Promotion: Anyone who is following you on Twitter is already someone who knows about you. Sure they want to keep up on any major announcements, news, and/or press mentions about your startup, but don’t succumb to tweeting  e-v-e-r-y  s-i-n-g-l-e  mention about your company! That will simply get people to unfollow you. Your followers should feel informed, not bombarded.

3. Announcements/Service Updates: One of the best uses of Twitter is for making announcements about new features, scheduled downtime, or even keeping your followers informed when there is some unscheduled downtime. Every startup has problems from time to time (Guess Twitter itself can be the poster child for downtime! PS the last two links are the most funny ones). We know this. Your users know this. What matters is how the company handles this downtime. Keep your users informed about what is going on. If you’re having problems, don’t be afraid to tell people that you’re sorry and working on fixing it. Posterous recently had a massive DoS attack against their service. Yes, there was downtime, and some of my personal sites were affected. But in the end Posterous emerged as the winner in my mind, because they did an awesome job of keeping users informed via their Twitter account (@posterous).

4. Engage w/@Replies: Even some seasoned twitterers aren’t aware of the fact that when you @reply someone, that response doesn’t show up for everyone. Twitter’s implementation of the @reply is such that only the person you @reply and any common followers (i.e. people who follow you AND the person you @reply) will see the response in their feed. (Note: Though if someone goes directly to your Twitter page they can see your @replies to others, they’re not private!) Mark Suster has an great explanation of this in his blog post: 6 Tips for Using the @ sign in Twitter. @Replies are a great way to engage with specific followers without bombarding all your followers with everything! If a user has a problem, you can @reply them and engage with them to help solve that problem. If necessary you can follow the user so that they can DM you to send any information that shouldn’t go over the public channel.

5. Monitor your Brand: One of the best things you can do with Twitter is to monitor your brand. You can do this by creating search columns in TweetDeck (or whichever Twitter client you choose to use. I use TweetDeck, but will also plug Seesmic for @loic). Here again you can potentially (yet, sparingly) use @replies to engage with people directly. (Another site which is very useful for monitoring brand awareness is BackType).

6. DO NOT SPAM!: The worst thing you can do on Twitter is spam people. Very often this happens inadvertently. As a young startup you’re excited about your product and when you see someone tweet about a problem they’re having — a problem that your product can solve, it’s natural to think that you should @reply that user and let them know about your awesome service. Well, believe it or not, in most cases users perceive this as spam. And yes, you may not think it is spam, but it’s their perception that matters. It hurts your brand. If you really feel like you want to reach out to that person, do it from your personal twitter account, not from the company twitter account. And if you do, do not peddle your product without getting the users permission or engaging them in a dialog first. For instance you can say: “@UserIDon’tKnow saw that you’re having a problem with X. I work for @MyCompany and we might be able to help. Please @reply us if interested.”

   Even this may be crossing the line if you do it too often — you really only want to do this in select cases and use your judgment to determine whether or not you should reach out to the person you don’t know.

7. Promotions: Twitter is great for running promotions to get the word out about your product. Even though Twitter #hashtags and “trending topics” are often what people target with their promotions, it is highly unlikely that you will become a trending topic. And even if you do become a trending topic, Twitter’s current implementation of trending topics is completely useless. It doesn’t tell you what that tag really means, and, it doesn’t drive users to an action. Your promotions should include a call to action, ideally a link that users can follow to get your product and/or your Twitter handle so that others can follow you. Also, encourage users to be authentic in their opinions. Don’t just have them tweet out a standardized message, but ask that they include your Twitter handle and your link in their tweet, but to share their own opinion (you can provide samples for the lazy!). Authenticity is a big measure of whether or not their followers will click through. If they know this is a canned message because this user wants something for free, they will ignore it.

8. Be RT Friendly: Limit length to ~120 characters, or technically speaking limit length to 140 – len (“RT @MyCompany: ”) so that others can easily Re-Tweet you without having to spend time editing the content to fit the 140 character limit. Event though Twitter has introduced new RT behavior, a lot of people (self included) prefer the old style RT as it maintains the source chain better. (See Mashable article on: Twitter Faceoff: Old Versus New Style Retweets).

9. Stay Classy: Inevitably you will encounter people who have a negative opinion of you and/or your company. While you should do everything in your power to address a legitimate concern, at some point you have to realize that you simply can’t please everyone. Whatever you do, do not get defensive and do not fall to their levels. In other words, “Don’t Feed the Trolls.” Always remain classy. Remember that anything you say is a reflection of the brand and image of your company. How you deal with a belligerent user will be seen by several other users as well. It’s an opportunity to exercise restraint and show others how well you respond.

10. Blog: Twitter is ephemeral. Tweeting w/o blogging is incomplete. The 140 characters on Twitter are good for driving engagement and getting distribution, but they don’t really create a lasting impression of you or your company. What does that best is a combination of blogging and tweeting – where you blog, and then use twitter to drive people to your blog. For example, when you make a video/tutorial, post that to your blog and then tweet about it. By just tweeting about it, that information gets lost very quickly. This is especially true because Twitter does a rather poor job of archiving and making tweets searchable. Their current search index only extends as far back as six days and while several people at Twitter have said this will get fixed, so far it hasn’t. (I’m using Tweet Nest to archive my tweets). By blogging, you make sure that your content is captured and cataloged in the right place. This way you can always refer to it later as well when the same question arises.

11. Be Real: People like to engage with people. Give your followers a peek into the inside workings of your startup. Moving to a new office? Share a picture. Launch anniversary? Where’s the cake? Have a quirky office culture? Share it. Show the people and the personality behind the company. Be real and have fun!

The above list isn’t meant to be prescriptive, but more so to help start a discussion about Twitter best practices. If you’ve found a particularly useful way of using Twitter for your startup, or even if you’ve been on the receiving end of a company’s misuse of Twitter, please share in the comments.

Thanks to all those who helped to proof read this post, especially to Sid Viswanathan from CardMunch (@cardmunch), and Ron Yeh. You can follow me on Twitter at @manukumar, or, follow @k9ventures for just the K9 Ventures related tweets.