Try to cut down on as much exstranious light by putting some form of sheeting around your observing position,such as tarp or black plastic.
as other posters have said use a cloth or hood over your head ,and use higher mag on some objects which help to darken the sky.
Contrary to some posts I do not think any filters are any good for galaxies.
Colour filters such as a blue filter are fairly good for the brighter planets
