put your dominant hand on the vertical surface with your fingers pointing downward at the ground. push down and see that you have at least some resistance that will help you hold yourself up. next, get your non-dominant hand and put it above your dominant hand, with your fingers pointing sideways. jump with your legs, up and in the direction you want to spin, use your hand with fingers facing down to pivot, hold yourself up, and spin on, while you use your hand above to spin yourself. i was taught to "spin the pizza". the wall is your pizza, being held by your pivot hand, and try to spin it like a pizza with your other hand, and what you are really doing is spinning your own body as you do this.
easy ways to practice. go a rail or ledge about waste high. and do that railspin where you jump and spin your body 180 degrees but land on the same side you started on. start on the end or corner so you dont clip your feet if you didnt spin or jump good enough. that is a good prerequisite. a way to practice the actual palm spin, go to a park with those big red picnic tables. rest it against a tree at a 45 degree angle. and start palm spinning there. once you get good, move it up to a high angle. the lower angle makes it easier to hold yourself up. as you get better, you can increase the angle by pushing the part of the picnic table on the ground closer to the tree, thus increasing the angle and difficulty. eventually you will be almost completely vertical. trying it on a completely vertical brick wall will just be a minimal difference from that point
good luck
---Scrag
