First find a chain saw, and a hand saw, and a high power wood sander.
Then find a nice log/ tree that you want to prep up, make sure it has no hard bark, because anything with a hard bark will be a waist of your time.
When you have that sucker all chopped down its time to prep, take off all the branchs off with the chain saw ( if your good enough, if now hand saw).
Now most of the time your gonna end up with little stubs, you can get rid of those with the sander, or the saw.
Now you need to go up and down the log/tree that your gonna ride and smooth out the part your gonna ride on.
Now like the gent said before you can use candle wax, or skate wax, or just keep it like that.
You would be quite surprised how quick wet wood slides, i never use wax, but your have to have your edges grinded down or your gonna be in some pain.