Thumb Casting Guards For Conventional Reels!
If you cast using braid & you're using big reels & rods, chances are either you may need to "power down" your casting distance or go to a lighter weight so your thumb won't get line burned. Casting with monofilament is safer for your thumb but you won't get the distance compared with braid.
Back in the day we used cut rubber rings from bicycle inner tubes as thumb protectors. What i've used for years are leather thumb protectors. Learned about these while i was in archery to protect your digits from skin damage. For years i've told this to many anglers but nobody took me seriously, until recently.
Using these leather guards will help your casting abilities. Casting farther may put that bait in the "right" area. Be sure to keep pressure on the spool. The line needs to be kept taunt, if it loosens up knotting will occur. I prefer braid over mono. More yardage for those long runs. You can put a mono top-shot to braid backing, many slide baiters often employ this line feature.
After 100's of casts latter you may not need to use casting guards. It'll help you save wear & tear on your thumb while you get your timing perfected.
(Good to wet the line & thumb guard pad so no line damage during the cast. Bringing a plastic spray bottle helps).