What do you try to do when you send a tweet? Do you have an answer to that question at all? The advice I typically give is to tweet with the goal of adding value to your community or desired community of readers. And that still holds.
There is a secondary goal, however, as a PIO. You want to add value but you typically also want people to take some kind of action as a result of your tweet. That action could take one of many forms and the specific action you want people to take depends on your strategic goals for communication, but here are a few possibilities.
1) Follow a link: You might want people to read a story you have written about your institution’s work, or perhaps a story about some other external work that you think is valuable for them.
2) Retweet: You might have enough information of value in the tweet itself that you just want people to spread it widely.
3) @reply: If you are trying to collect information or provoke discussion, you might be trying to garner replies. This is often easiest to do with an explicit question in your tweet.
4) Do something outside twitter: Perhaps you want people to write to their congressional representative or take some other kind of action offline. They won’t know what you want them to do if you don’t tell them however. It’s best to still frame this in the context of how it adds value for them though.
When you think in the context of trying to inspire action, you’ll find that your tweets naturally tend to add more value for people as they give people something to follow up with. However, be very careful that you’re not doing it selfishly, and make sure you are always adding value for them.