I rarely use anything but mouth calls, although I do carry a pot or two when hunting. For those friction calls, after the season I do a quick inventory of the calls and strikers to see what I have either broken and/or lost and put away what has survived my escapades...generally until right before the next spring season at which time I will sort through them to see which pot/striker combinations I will most likely lug around with me unused when the season starts.
The mouth calls get stored away after the last hunt in the spring, which is usually in the latter part of May. I will disinfect all the mouth calls I have used and store them away in the fridge. Generally, they will not be touched until after the first of the year sometime. I will usually start getting anxious in anticipation of the upcoming spring hunts at some point and start sorting through my "fridge" mouth calls and making new ones. On average, I would say that process starts a couple of months before my first hunt.
Outside of that, I don't practice much any other time of the year. I suppose I have concluded, after all these years of trying, that my turkey calling ain't gonna get any better with more practice and I might as well resign myself to that. My fundamental theory is to find a gobbler or two out there in the turkey woods each spring that think my calling is good enough as it is. That theory generally works well enough to suit me.
As for those gobblers that think my calling sucks...well, I just leave those for you guys that practice a lot and can kill them!