hi guys, back again with a couple more questions, everybody was helpful and if i knew how to +rep i would

i ordered my first piece, a glass pipe (your standard spoon) about 10 days ago and it came in today, so i just have some in-general questions. i think i'm gonna keep the bubble-wrap it came in to hopefully prevent any accidents, we'll see if that helps...

1.) screens. these are a necessity to prevent the weed from falling down the hole, right? can i substitute them for something else around the house, or should i find a headshop and buy some?
2.) homemade waterfall bongs. does the presence of the water cool the smoke like a normal bong? does the smoke lose any of its thc/potency when it's just chilling as the water level falls?
3.) resin. if i'm not looking to smoke it, is the best way to deal with it with a paperclip? or...?
4.) anything else about taking care of the pipe that's not obvious? thanks.