The mechanics are just easy:
1) All you need to do is leave a comment on her post, it is easier for her to keep track of the entries.
2) You MUST leave a way for her to contact you, If you have a blog, She can click on the link when you post. If you do not have a blog, then just leave your email in the comment. She is not harvesting your emails so just don't worry about spam from her. If you feel better put spaces in the email.
3) If you want to be entered a second time, all you need to do is put a link to the purse give away on your blog, and let her know that you have done so and she will enter you in twice! That's it!
off to check out the linky loo