I tow in D - however at the speed I tow my trailer (1800KG) that equates to around 1850rpm in 6th - therefore if I am on a hill I will knock her down to 5th to avoid the engine labouring.
Correctly loading the trailer RE noseweight - is important.
As for reversing - take it slow and steady, and use your mirrors - and have someone to help. To make the van turn you need to turn the wheel the opposite way to which you would normally do for the car, once the van has turned about 1/2 the desired angle you need to get the car to follow the van - so turn the direction you would normal turn.
You should then end up where you want to be. Your best bet is to get out into an empty car park and practice as much as you can - otherwise you will first need to reverse when you least need want to.
I can pretty much do it now without thinking - but the biggest tip is TAKE IT SLOW.
With a little practice you should be able to parrellel park with a caravan on the back
