for tables i was just shown a really good tip, and thats to swing the front of your bike towards your forward foot while getting your knees together, then snapping into the table. its so much easier this way. most important thing is to keep those knees together as your not fighting against your forward foot with your hand movements.
basically move both your arms to the side, the same side as your forward foot, then do the table. that helps get your knee over the top tube, and also gives you more leverage for some reason.
a good way to barspin and keeping the legs on the pedals is the do half barspin first. its easier to get the feeling that way and if you know how to do that (which is a day or two of practice) you will do full barspin in no time.
try some tables, euros, 1 foot euros, nacs, x-ups, different styles of whipping and just staying loose and whipping the bike around in the air. watch bmx trails vids and stuff and just try tweak the bike like they do. its good for bike control to help with harder tricks, and just feels awesome.
im not doing tricks on the trails yet, but im whipping the bike around in different ways and theres actualy a lot you can do and it teaches you a lot as well.