It is important to stay active on Twitter. If you dont tweet enough then your followers could get bored of you. The more active you stay, the more visible you are to users who are not following you and the more interesting you seem to those who are following you. It is important to put quality in front of quantity. Because if you are tweeting constantly about nonsense then you run the risk of looking spammy and actually annoying your followers by filling up their timeline. I personally tweet on average about twenty times a day. That may be too much for some people but you have to find your own balance and that will take some experimentation.
When Should I Tweet?
There are a lot of different theories on when is best to tweet, because followers can and usually are scattered all over the world. I suggest you first find out where your followers are by using this tool, http://www.mapmyfollowers.com/. Using this tool will show you where the majority of your followers are from and then you will know when the best time to tweet is. For myself, my followers are divided by the UK and the US. The numbers are very close in regards to how many on either side I have. So as a result of this I need to entertain my American friends as well as my native UK residents. To combat this, I schedule tweets for times that I would be unavailable to tweet, like 8 PM or later, but these scheduled tweets do not have to be unique, you could have tweeted them earlier that day. Whenever I tweet a link or news story, I schedule it for 12 hours later to account for people on the other side of the world. This method means I am active 24 hours a day even when I am not even at my computer. If you are not sure how to schedule your tweets, there are a tonne of social media management suites, one of which is Tweetdeck, which I have written a review for, - this and other management suites allow you to schedule updates for later, which is an amazing advantage for many. A general rule of thumb is that prime time is at 4PM UK time, because everyone in the UK is about to leave work and everyone in the US has just started. 4PM is the best time to make the maximum amount of impressions.
So the next time you tweet, make sure you take all of these factors into consideration. To get this right, it does take practice, but you will eventually get the hang of it and understand your audience more and more as time goes on. Twitter requires patience for followers to grow and for your profile and techniques to develop, but once enough time has passed, then you will see the benefits.