There are a series of skills that you really want to master prior to doing a Handstand, Handstand Push Up, or Handwalking. I know, I know - you're way to "advanced" for the basics... are are you? I know of several athletes who can't do a Headstand but they can knock out something that looks like a Handstand Push Up. Unfortunately they don't have the strength or motor control to do the movement strictly but instead resort to contortionist-like movements or unsafe techniques to get a "rep". Is it really worth it for short-term glory when you are still going to be weak long-term? I don't think so and I won't coach my athletes that way either...
Take a look at the following video on the Headstand. Yeah, yeah, yeah... the Headstand is too easy for you but check out the video and see of you can do all of the variations with control and good integration. There are some good points on how to prep the position, load and unload, as well as some progressions and regressions. I know the guy - he seems to know what he's talking about...
BTW - next up will be a video on how to train to get into a Handstand without needing the wall to save you. Remember - all of your training should be geared towards developing skills that are at the advanced level; not skills that are advanced at the beginners level.