easy peasy
a lightly moistened cloth (I've just discovered microfibre !!!!! bl**dy marvelous - don'y know how I've survived without them!!)
If you have more than just dust ... a drop (literally a drop .... no more) of pure soap (the stuff for washing wool is excellent)
Turn off - let the screen cool for 20 mins
wipe with the cloth ... if stubborn .... leave damp .... repeat
then dry with another cloth.
don't be tempted to use elbow grease ... or grease remover ... the front is very fragile ... scratches and ruptures at the drop of a hat