Site location can be important, look for sites that are naturally hidden anyway....depressions that could hide a camp site (but be aware you'll need to compromise as water may collect here too) other dead ground, dense thickets etc.
Short term it might be possible to buy cam netting and string it up behind natural foliage to beef the screaming up a little but it does mean carrying a cam net. Longer term why not plant something native and already there in larger numbers to grow your own screen? Can't advise cutting fresh vegetation for screen as its destructive and as it dies it then
looks more obvious that if you hadn't used it at all.
Most of the time if you are subtly dressed, very quiet, don't move much and try to burn smokeless fires then nobody will notice you anyway.
If of real concern then maybe set up a few early warning systems....snapped branch over the trail a little way up or trip wires with cans if you're feeling a bit "MacGyver", and then when you are alerted to somebody close by you can stop what you're doing, stand very still and watch whoever it is come and go without noticing you at all. I'm lucky in that my dog will give me a few very quiet woofs when somebody is close but doesn't go batty barking and shouting unless they come right into camp uninvited.
Hope that helps....not a great help I know but it's a long while since I had to hide from anybody in anger! Lol
Cheers,
Bam.