First off, let me get out of the way that I don’t believe in meditation as a ‘spiritual’ practice, as every moment of life is a spiritual experience. This is why I get annoyed when BJJers put a halo over training. A black belt in Jiu-Jitsu is NOT a black belt in life. Politics permitting, it means some one awarded a symbol recognizing a degree of knowledge at a particular time.
So, ranting aside…
The initial rule is, hitting positions over and over in a way that works for you and your circumstances. Really, repetition is an idea, not a weird trick, so approach it as such. The problem with just sparring is we’re leaving what gets refined to chance, and that’s not really training. Training implies objectives.
In terms of types of reps, dead reps with little or no resistance require the most concentration:
So, the basic idea for dead rep meditation application is picking ONE specific area within a position you want to improve and using it as a mantra.
Indicators that we’ve moved away from said mantra are excess tension, wandering thoughts, and/or focusing on details outside of intended objective.
One thing at a time.
Lastly, to re-iterate, we’re doing these things to train a specific skill-set, not ‘become’ a better person. So, enjoy yourself and don’t make things harder than the need to be: