Repeatability is key,
a 90 is 90 degrees,
you overbend it a little (spring back) to get there and check it against a known 90.
Being able to make the same 90 over and over helps,
then you learn how to bend an offset (two equal bends in opposite directions)
then 4 bend saddles (two offsets)
then 3 bend saddles (more difficult saddle).
Then understanding why you might want one type of offset for one application,
but not another.
Planning ahead for multiple runs,
or trying to fit into an existing place where the last three guys didn't plan ahead is what comes last.
Eyeball the pipe to make sure your bends line up correctly,
or use pipe with a straight line on it to help line them up,
or use a "no dog"
^little clip on 1 bubble level to make sure you spin the pipe exactly 180 degrees when turning the pipe over for the next bend of a saddle or offset.
Take your time,
try to figure out how you made a mistake of you don't like how the piece came out.
If you are kinking it you might not be putting enough pressure on the back of the bend,
or trying to make too big of a bend in the air.
Being able to bend the same bends the same exact way over and over is 50 percent of being good at piping,
the rest is knowing what bend should be used and where,
and being able to measure correctly.
Don't get frustrated,
no one starts out great at it.