what's the most crucial aspect to fiberglassing?

After reading posts and looking through numerous websites, I recently completed my first fiberglass project.  After finishing and reflecting, I noticed that there were a lot of things in hindsight that could have been done differently to save a lot of time.  For my benefit and others who are new to the process, what do you feel is the most critical or crucial aspect to fiberglassing in order to be efficient. Or is there advice you feel everyone should know before starting a project.   All thoughts welcome.

Preparation:

• Have at least 1 Box of disposable gloves on hand, latex, rubber, whatever, but Nitrile gloves work best. BTW if the gloves are too big they're completely useless, which I found out the hard way (they slide right off when sticking to wet resin).
• Brushes: I know walmart sells a variety pack of 4 or 5 disposable brushes for just a buck or two, best value I've seen yet. After getting them wet with resin, you can have a cup of acetone to keep it usable for a couple times, but this doesn't work unless your gonna be using it pretty soon, and wipe the brush out real good with a paper towel after taking out of acetone.
• Cheap small disposable bathroom cups. Use these for resin and for the acetone. Plastic or even some of the others will melt under resin, it's an experiment.
• Long small diameter wood dowels from home depot or the like are excellent cheapo mixing sticks, break to just the size needed, and your set.
• If you want to peel the glass from what you're laying it on, blue painters tape from home depot works excellent.

Technique:

• Put on the gloves before you open the resin and until you have shut it up and thrown the cup away :D
• I have yet to ever add too much hardener that it screws up, it just dries super fast, but too little may cause it to stay gummy for more than a day...
• Use the brush and brush a thin layer of resin over what you want to lay it on to get it sticky, put the cloth or mat on and make sure most or all air bubbles are out, if not all the glass is transparent, which it shouldn't be, dip the brush with resin and dont brush the resin on, dab it vigorously all over the mat.

I have much much more, but my glass is dry and I need to lay some more, I'll be back with more, hope these help.