You are very wise to get in some good practice with varied routines. I'll share my story and thoughts on prep and practice for my son & I from last year.
At the end of 2023 I booked my son and I on a May 2024 hunt to South Africa for a buffalo cow culling trip, he was 21 at the time and had a new Blaser R8 in .375 H&H. I had him shoot at least a total of 200+ rounds for practice, over several months, (initially not all full 300gn factory loads). We found the life sized buffalo target invaluable. We also planned to shoot some plains game animals on this trip and wanted to learn how a .375 would shoot over distance. I joined him with the practice and probably shot 120+ rounds myself.
Bench shooting was only done to zero the rifles, all of the rest of the practice involved mainly shooting from sticks and free standing. I made sure we also did some shooting from sitting, kneeling and prone. We did some "rapid" reloading sequences with first shot on sticks and then several rapid follow up shots free hand standing. I had my son shoot from 50 yards and extended his range back every 50 yards back to 300 yards, he was responsible for producing a small bullet drop card that he carried and memorized so he fully understand how his rifle would shoot over distance. We also took the opportunity to use our scopes and the life sized buffalo target to try to be able to do some range estimation.
I was the proudest father to see him take several buffalo and other plain game with well placed shots under difficult shooting conditions that involved lots of brush and limited views of the animals.
I did my fair share of practice with him and I really struggled on our hunt in South Africa with my PH to get in close for a shot on an old buffalo cow, after several days my only option on the last day of hunting was a 220 yard shot, swirling winds and thick brush had made life real difficult to get in close for a more normal range shot. My PH was not sure about taking the shot due to the distance but I told him I was very confident in taking the shot, he relented and allowed me to take the shot. My practice with my son had made me very confident shooting my .375 H&H back to 300 yards. I managed a perfect top of heart shot from the PH's sticks. That pre hunt practice sure paid off for both my son and myself! We ended the trip with a total of 3 buffalo, and several plain game animals, all one shot kills. I shot 1 round during the entire trip for that 220 yard buffalo, I would not have taken the shot without all of the extensive practice.
The cost of ammunition used during practice was negligible when you considered the overall cost of our trip. Previously most of my son's hunting had been Michigan woodland based where shots are rarely over 100 yards. My son was already extremely proficient with a .308 for deer woods hunting but the practice over increased distances with a much larger caliber rifle really taught him something that he will use as a basis for his many years of future hunting. As a father our practice trips were all great bonding time between us both. This year in May we are off to Australia on a large quantity culling trip of buffalo, pigs, donkeys, camels and other animals, as soon as the snow clears we will be back to our practice trips to our private range on our North Michigan Hunting ground. My son will be repeating his .375 H&H practice but I will also have him shooting a lot of rapid .308 on multiple targets over a shot time window, those camel culling videos from Australia show some crazy action!
I'm back to needing practice as I have a new to me 500/416 NE double rifle that I'm planning on using for a fair number of Australian buffalo!