It's funny, when i read your question at first, I thought of discipline as in ways we add structure and discipline to our lives or our D/s relationships - I didn't think of it as punishment. So easy to cross the two ideas, especially in western culture where often discipline feels like punishment and punishment is used to instill discipline - and in BDSM culture where the same activity can be used either as discipline or punishment with a very different feel and outcome based on its purpose (could make for a good discussion thread).

I'm still unsure of exactly what you're asking so I'll throw my two cents in the mix here and maybe it will land somewhere near the mark.

I'd echo the positions training that was already mentioned, but add in other types of rituals too like the use of mantras or setting rules around activities (like asking permission for basic needs/wants). Maybe look at an activities list to get ideas too. So many activities can be used to expand limits and tweeked to be used in a manner that adds the element of establishing discipline.

I'm fairly new to all this so I don't speak with great confidence in what I shared, but trying to get more involved and add what I have learned / am learning. Hope it helps.