Two things to keep in mine as you spool. One is to ensure you don't overfill the spool. Watch the line, if it is touching the top of the reel, you are way over filled. This can happen quickly when using heavier line. When using light line, stop filling at the beveled edge. When using heavy line, 17lb. and up, stop filling 1/8 from the bevel. This should give you plenty of clearance.

Two is to strip your existing line back far enough that your connecting knot is well into the core, so that if you do break off, the knot doesn't expose itself. Knots are notorious for catching your line in mid flight and your lure ends up landing way short. The knot can also create back loops and backlashes. In cold weather, that connecting knot can slice your thumb if you are not careful. You don't want your connecting knot to be places on the side of the spool. This can create a pincher point if you backlash and become a real pain to straighten your line out. You don't want it dead center either. This will hamper your thumb pressure. Somewhere between the edge and a quarter is ideal. No knot to contend with is best.

Always backfill your spool, but doing correctly will save you money and hassle!