Once you receive a term sheet, it will include a deadline on when you have to respond. Usually these are fictitious but you don't want to let a deal go cold.

You'll have a limited amount of time to determine if you should take the deal (while you'll still be trying to collect more from other investors).

Make sure you have people you can discuss the term sheet with who have some experience in this process. Your counsel should have experience and you may have other informal advisors or know entrepreneurs where you can get advice. Make sure you understand all the terms and determine if (and where) you have some leverage.