My advice is don't bother!!!
I'm no idiot and have tried all ways to get the new belt on without success. Wasted about half a precious day off plus the cost of the new belt. Went and got a new dryer today for £130.00. Mine was a Hotpoint VTD00P with 5 yr parts warranty, (yeah but about £80.00 call-out apparently!
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix tumble dryers.