Hey Kitty! You have to be 18 in most states to enter a tattoo shop, so 18 could be considered the age requirement for being an apprentice. What you do is go around to shops and find out if anyone has room for an apprentice. The shop will usually charge you about $2500 and you have to work for free, for tips or for very little $ for about one to two years. Every shop is different. I know of one shop here in TX that charges $10,000 and makes you work free for 3 years!!! Once you have your apprenticeship done, you will have a decent portfolio, then if you can't or don't want to stay at the shop you apprenticed at, you can take your portfolio and find a new job! What I DON'T recommend is getting some equipment and just tattooing out of your basement or house until you get a portfolio together. Safety and sterility are very important and you don't want to risk anything, especially your integrity. Good luck!!