What should i put in my tattoo portfolio
One thing NEVER to put in your portfolio if you are trying for a tattoo apprenticeship is any reference to tattoos you have done, or do not show any you have done on yourself. The pro's hate "scratchers" and see it as though they are going to have to teach you twice due to having to get rid of your bad habits first.
Otherwise, just put all your best hand drawings and/or paintings and set them out nicely in a portfolio organiser.
Take a photo of your stuff set out so that you can leave a copy with them. Anything really, just to put you above the rest.