Also at this point in time there is so much shady stuff going on with options that you should always always value options at zero. Frankly if all you are offering is your labor in return for options you don't have the pull to get a particularly good deal. (Example: Friend worked three years at a startup. Friend is smart. Friend got ~$50,000... whoop dee doo dah day)
Only other advice I have is, if you are considering exercising any stock options you need to talk with a tax accountant before you pull the trigger. No exceptions.