Boosterforum is not a tool to creat forums: it's directory for forums which are already existing, it provides services for both readers and writers.
First of all, you should keep in mind that everyone will be allowed to read your threads and to discuss the opinions you are submitting. You will have to spend a certain amount of time to check and to keep your forum alive and interesting
Then it will be better for you to choose to talk about something you are really into in order to keep your forum regularly updated. The frequency of your updates will create an evergrowing interest for your readers, they will grow in number once the word is out! The name of your forum is very strategic too, because it will arouse an interest, or not, for readers to click on it. Direct or mysterious, it's up to you, but dont forget it will end among thousands of other forums!
Do things simple and clear, for the visitor's pleasure it should be a good mix between serious and recreative topics. You can invite them to post new topics in order to show that your forum is a lively place. Get it known and you will surely find people from all horizons sharing the same interests and passions than you ! You could, for example, share some links, do some visibility trading and display on your forum the list of your friends who are forums owners too.
With Boosterforum, you will be able to see if your forum is at the real mesure of your expectations with the votes of your visitors !