Oh hello, I'm new here!

I came bringing some questions on how to make icons like these:

#1 by tolerancewrong

#2 by tolerancewong

#3 by nothingnewtosay

I should be very much obliged if you helped me with these. I'm most interested in the third one, because I tried to make it, and what I got was that:

and these are not exactly what I wanted...

Thanks in advance!