Parents+tattoo? Help!!!!!

Renée • Bohemian girl just living life 09/29/17 R.❤️

How do I convince my parents to let me get a tattoo? I just turned 16 on April 13th 2018 and I don’t know how to ask my mother if she would let me. This tattoo that I would get is very important to me because it is the reminder of one of my best friends who passed away from suicide on may 4th 2016. The two year mark is coming up and I really want to get this tattoo to remember him. A LOT of other people my age have tattoos but I really feel like my mom is going to say no. I don’t know what to do or how to explain to her how important and special this would be to me. I want something so that he’s always with me through life always there right by me. Some please help me get ideas on how to bring this to my mom.