Routine and practice are the key.
Doing the same things in the same order each time means a lot of it will effectively become muscle memory, from completing the walkaround to checking the weather, the more you practice when you're not flying the better.
Back in my low hour PPL days, I found I always checked the aviation weather sites while I was at work, or in the evenings. This gets you very familiar with where to find the info, so it takes far less time when you need it. Do the same with NOTAMs and you've instantly sped up your pre-flight prep.
Just keep practising and thinking about these things while you're not flying, even taking a few minutes each evening to "arm chair fly" where you just picture everything you need to do pre-flight to get the engine running, power checks complete, and then post-flight actions.
If you're serious about going commercial, I'd be practising these things at least every other day to get them running smoothly. Even on my commercial type rating we had a cardboard cut out of the aircraft with all the switches and buttons. We were told this is where we should learn all the procedures so by the time it comes to the sim/real aircraft it's just practice.