In reply to lynda: Firstly only try one new thing at a time. If you go out & try to do 3, 4 or 5+ new things at the same time you'll have difficulty getting the hang of any of them and probably enjoy it less. So just work on one at a time till you get the hang of it then move onto the next one.
Don't look down look ahead. You shouldn't be looking at where your front wheel is you should be looking 3-6+ metres in front.
Drop your heels. When you have your heels dropped it tends to put your weight back which makes it easier to role over obstacles.
Speed is your friend. It's much easier to get through stuff when your going faster. The faster you go the more inertia your wheels will have. The faster they spin the more they'll want to stay upright & going forward through gyroscopic action. It's very hard to do & i suffer from it myself but it's often safer & better to roll through obstacles with speed rather then slowly.
stay loose/don't grip the handlebars too tightly You don't need to hold onto the handlebars very tightly when riding. If you do, you'll tend to find on longer descents & runs overall, your arms will get pumped. This means it's harder to manuevre the bike around to avoid obstacles. Gripping the bars less tightly will stop this happening or at a bare minimum slow down it's affects. Also staying loose means you will be better able to recover when you hit any unforseen obstacles.
don't be afraid to man/woman handle your bike. If you use your upper body & balance more it's much easier to avoid a lot of smaller obstacles than just trying to steer around them. A lot of the time it can be as little as leaning to the side to just deviate your line the smallest amount.
Should be enough for now but if i think of any more obvious ones i'll post again. In the meantime enjoy it, it's great fun.