For ease of mixing, I put 1 cup or oatmeal and 1 cup of cornmeal in a large mixing bowl then add the peanut butter, then the rest of the ingredients.(This keeps the peanut butter from sticking to the bottom) But the order will not change the outcome.
I use a pastry blender to cut the peanut butter into the other ingredients but if you don't have one, a spoon works well also.(just a little more effort) Cut or mix until the peanut butter is well incorporated. (See photo)
***If you want to add variety you could use peanut butter and shortening or lard. Add sunflower seeds, sesame seeds, or fruit and nuts. This is just a base for amounts and low cost and I have many birds that like it as is: Chickadees, Nuthatches, Woodpeckers, Cardinals, and finches to name a few. I put mine in a tray feeder but I'm sure if you added more fat to it you could form it for a suet holder. Enjoy making some new friends!