Sounds a bit funny, but try this. Whenever you can, practice picking a spot. Your neighbors dog walks by, pick a spot and concentrate, the cat, the bird, etc. Not just while holding a bow, but anytime. I also like to approach full mount animals, especially at panoramas like at Cabelas and Bass Pro Shops, and just sit and look at them and imagine. Pick a spot, feel what it is like to be that close. I find that it helps, maybe, if nothing else, because I am now used to picking spots on everything. Heck, next time your boss walks past...( I didn't say that did I ?)
Chuck