1. a couple of great items for making/fixing things: super glue, twist ties, duct tape, hockey tape, zip ties, rubber bands
2. if you bring a fishing pole with, and it has cork handles, load them with polishing compound....not only does this help your grip when the handle gets wet but it makes a great strop for fillet and other knives
3. if possible, spool your paracord instead of just folding it up....this will save a tremendous amount of time since a bundle of paracord can tend to become a spiderweb of cord really quick
4. this may be obvious but rolling your clothing will allow you to pack more as well as keeping things from wrinkling
5. combat rolls are great....take two socks and lay them overlapping horizontally so that the toe on one sock is touching the heel on the other....then lay a t-shirt folded in half lengthwise on the ground and then lay a pair of underwear on top of the shirt....put the overlapping socks towards the top of the t-shirt/underwear and roll it up like a sleeping mat.....the socks should be sticking out on both sides....then fold each side of the socks over the roll like you would when you bundle a regular pair of socks....this will not only condense the entire bundle but it makes finding a change of the essentialls easier to find in your pack
6. having two belts is a nice way to go......one belt is through the loops on your pants and is for holding your pants up...the other is not through the loops and its where you attach all of your gear so that if it sags it won't pull you pants down too.....when nature calls its much easier to just take the outer belt off
7. along with #6....a couple of qualities that make the outer belt even better: quick-release buckles and pull-to-tighten adjustment.....and even one better is a fanny pack that has those two qualities so that now you have a built in pouch
8. if external frames are your thing(they are for me), it goes without saying that the exposed frame areas are great for attaching much used gear: knife sheaths, camera cases, duct/hockey tape rolls, spooled paracord, first aid kit, etc......granted this makes them more likely to catch on stuff but an external frame is usually that way anyway....this opens those pouches up for important gear like flasks