I can give you a couple of pointers but you are far better off watching someone do it. Lots of tricks to it.
I use a high temp contact cement made for gluing vinyl top to cars. If it holds black vinyl in the sun it is good enough for me. It is made by Weldwood.
When working with contact cement heat is a big help. If you stick something down wrong a gentle application of heat will allow you to peel it back.
The best thing I ever learned from the best upholsterer I ever know was that leather stretches in one direction better that the other. Align your cuts to take advantage of that. In other words figure out how you need the leather to stretch and cut you pieces to take advantage of the leather’s stretch.
The leather must be Skiived or Split in order to be successful. Splitting is the process of making the leather thinner. Think glove leather and not upholstery leather.
That's what I have. I am sure there are Youtube videos. Try searching, “Covering door panels in leather”. They may not split the hide but you have to. The angles are too tight.
