There are a number of ways I've seen this done.
For single word items, I suggest either use no punctuation, or use semi-colons, with a period for the last item. For example:
You could use the same type of structure for sentences as well:
- I am happy;
- She was happy;
- He is happy still.
Alternatively, use full punctuation for single sentences.
Likewise, if each bullet is more than just one sentence, then I would follow full punctuation rules, since it's quite clear that I'm using bullet points for a very complicated list of items.
Having said that, however, as Lauren says, it's best to ask for the house rules first. And the number one rule is: be consistent in whatever you choose.
Edit: I found this article which you may find helpful: http://grammar.quickanddirtytips.com/formatting-vertical-lists.aspx
Most of the article is based on a book called the "Chicago Manual of Style". I won't duplicate what is written there, but it is extremely comprehensive. Also, it's worth pointing out that, while the writer doesn't like the usage of semi-colons, in a footnote she says, 'commas are optional in some lists and allows the conjunction and after the penultimate list item if you are using semicolons at the end of each list item and closing the last item with terminal punctuation'.