Well! I have discovered that needing to buy a second loom is simply an early stage in the addiction. I now own six looms. Yes, that's correct, SIX. Since I own some knock-off looms, I am shopping for more of the Rainbow ones.
On to the tips.
When loom shopping, don't go anywhere near the knock offs, no matter how
close to the original they might appear. It isn't worth the
aggravation. (Trust me on this, been there, done that.)
Flipping the rubber bands into a figure eight is a bother. I just loop the rubber bands onto the pin that is farther away from me, then turn my hand over and loop them onto the closer pin and get my figure eight much faster.
To avoid bending or breaking hooks, remember to slide the rubber bands to the thicker part of the shaft when doing things that require pulling and tugging.
Rainbow Loom C clips are better than the S clips that are found in off-brand rubber band packs.
The more complex patterns that create wide, dense bracelets use up an astonishing number of rubber bands. Getting extra of black and white is a good idea.
Learn how to attach a button closure. It's worth a few failures.
Expect failures when learning a new pattern. Take your failures apart and try again.
Stretched out rubber bands from failures are fragile and break more easily.
Not all rubber bands from failures will be stretched out and fragile.