What is the best way to remove handmarks of a wall?

Try mild soap(dish) and warm water.

Mr Clean Magic Eraser

I found the best product that really works on anything and it is inexpensive. It is called mean Green Super Strength Cleaner and De-greaser it is made by Chem-Pro and you can find it at Wal mart. It cleans anything. Just make sure you keep it out of the reach of children. I know there are Walmarts in the UK so I hope they carry it, if not, try ammonia and soap it works too.

Go to the local grocery store and find the cleaning aisle. Get something called the Mr. Clean Magic Eraser. They come in little boxes. Buy two or three of them and go to town. The things really, really work.

Try Mr. Cleans Magic Earse. It's works

Those Mr. Clean magic erasers are miracle workers. They can even get the grime out of the little cracks on the fridge handle.

Mr. Clean magic eraser. It gets my kids "artwork" with permament marker off the walls!!! Its awesome!

Formula 409 works really well for me. They come right off with ease.

put your feet in a tub of red paint and walk all over the walls, hahahaha, Andy, how are you?///////// Nice avatar!!

Kaboom cleaner works good.