Fresh line and a full spool is the trick. No doubt in my mind. Anybody who says casting with a half empty spool ain't done much fishing I'll tell you that.

Mono line gets wavy after it sets on a spool. The closer it gets to the end the tighter the wave is. This makes your line come out in worse spirals creating way more friction.

Braided line helps big time. It doesn't get all wavy like mono line does. It's smaller so it weighs less.

Remember if you use braided line to get a pole and reel designed to handle braided line. Braided line will tear up your eyelets and reel if it's not set up for it.

A longer pole also helps get more distance on your cast.

good luck