What things to take care of before starting?

So far, I've just been painting friends and family at parties or on camping trips, etc.

A family member who owns a company is having a festival to promote business next month and asked if I'd paint for him. I agreed and agreed to do it for no fee. I was planning on putting up a board with a few of the faces I can do quickly and are popular and charge for those faces since I don't want to work for tips after reading the warnings here, lol!

Anyhow, is there anything I need to do before I start painting? I'm very ignorant when it comes to business matters and money matters (I am definitely a right brain kind of person and have a very hard time with numbers, etc). Should I have a business license?

For a total newbie who has never gotten paid, are there a list of basic rec's? For instance:

1) get license
2) get insurance
3)save receipts
4)????

Or if I'm not really even sure if I want to make this a business but maybe just do things once in awhile should I even bother with any of that?

Help!

a lot of these things depend on where you live as to whether or not you need them.... insurance is a good idea, but you might want to wait a little to see if things take off first? Definitely keep a little spread sheet of your income and expenses.. both for claiming income later, but also for yourself to see if you are going up or down in teh money dept.

If you are painting for this company as a favour and are not being paid ask them to check THEIR liability insurance related to to the event they are holding as it might cover anything you do on their behalf.