Have you visited the DIY forums? That's where all the help will be....and you CAN do it. I mix my own stuff. You will need nicotine
juice, PG and/or VG, and flavoring. You'll need empty bottles to put it in. You'll need some way to measure it....syringe or pipettes...something.
Do you have your nic juice and flavoring? You'll also need an ejuice calculator....there are several on the DIY forum.
Good luck....it's fun. I'd suggest mixing small amounts at first, let it sit overnight (to steep), try it out...if you like it, make a bigger batch.