I have ear canals that don't work well with 95% (or more) of the ear plugs on the market.
Pretty much all that works for me are good old, basic, cylindrical foam ear plugs.
Currently, there are two versions that I use:
E.A.R. 310-1001 "Classic" yellow plugs.
3M Tekk 90579 (Color varies - usually orange).
Both have an NRR of 29 dB.
Both of the above are owned/made by 3M, now. The 'classic' version is sort of the 'budget' option and are a bit stiffer than the 3M-labeled version which is always reasonably soft.
The 'classic' isn't much good in the winter (though that probably won't matter at an indoor range).
The 3M version is a bit more expensive, so I reserve them for cooler temperatures or winter shooting.
Outdoors, especially if shooting primarily rifles, I generally just use the ear plugs.
Indoors, or if shooting primarily handguns, I generally double up the hearing protection. (Some NRR 28 dB muffs from MidwayUSA or some Walker's Game Ear electronic muffs [26 dB?].)
....But no matter how much I do to reduce the noise level, there isn't much that can be done about the concussion - and that's what gets to most people.
You simply have to learn to live with it.
And if that can't be done... go to an outdoor range.
I have days when I seem to be more sensitive to the concussion than others. And, sometimes, you're simply facing an enemy that can't be tamed ...like someone shooting one of the large Weatherby Magnums next to your position, with a gigantic muzzle brake that channels the muzzle blast directly at you.
Sometimes, on days like that, I have to either walk away or wait for them to finish.