mountain biking - post ride tasks After completing a long mountain biking trail (complete with lots mud and water etc) - what post ride checks / tasks should I be doing?

I ask this because I don't want to be taking my bike into a shop to be fixed just because I've not been maintaining it properly after a ride.

Thanks.
Clean everything up and lubricate your chain. Wash the suspension and make sure the seals are fine. If you have a rear suspension pay attention to the pivots. For the rest it will pretty much be covered in a pre-ride check.

Check out the questions tagged cleaning here on Bicycles SE to read some interesting information on how to clean different parts of the bike.