As the year progress, I've found my eyesight is less able to deal with teeny little details (like PE), and my fingers are becoming less and less nimble.
For my eyes, I've found the magnifying visors are a saving grace. They let me see the PE pieces as I fumble around and flick them through space.
Then I made a discovery that saved many PE parts for me. I took a skewer (or you can use a toothpick, or whatever slightly grainy stick you want) and put just the smallest sliver of blue-tak on the tip of it. That's the stuff that stays forever soft, and leaves little grease spots on wallpaper when used to hang posters. With a little bit of this sticky stuff on a stick, you can use it to pick up the tiniest PE parts, and glue them where they need to go. Put the part down, let the glue set, and with a little twist the part stays put and the stick is ready for the next piece.
Another tip is if you're using the steel PE parts, as provided by Dragon, then magnetize an xacto blade, and then that can be used to pick up and position PE. As with the sticky stick, the magnetism is weaker than set superglue, and pieces stay where they're put.
As for folding, I finally broke down and purchased one of those folding tools. It's made such a huge difference, I wouldn't go back to building without it.
Hope this provides at least some helpful tips.
Mika