Aaron Wilson:
At some point - sometimes after one minute, sometimes after twenty - that subtle tickle in my nose "expands" to feel like it's "the size of my head," which doesn't really make sense but is the best way I can describe it. What was previously delicate and indistinct suddenly becomes big and obvious - it's sort of like starting on a faint, staticky radio station that you can barely make out and then then tuning it into full blast stereo. At this point the breath is so big and obvious that paying attention to it is effortless, and everything else (thoughts, sounds, leg cramps) fades into unimportant background noise.
Once you're there you'll probably start feeling really terrific for no particular reason. Investigate that feeling and see where it goes!
Excellent description, Aaron.
The "access" part of it is the "staticky radio station that you can barely make out." You've gained access at this point. The first jhana is "the breath...so big and obvious that paying attention to it is effortless, and everything else ... fades into ... background noise." In order to go deeper, you just have to calm down any further movements of the mind (
piti and
sukha) until you reach the fourth jhana, which should be very quiet and tranquil where the mind becomes stable, established, and workable. Reaching at least the fourth jhana should be your main goal. This allows the mind to begin becoming reconditioned. It also increases one's ability of concentration, which eventually extends long after formal meditation.
It all becomes quite obvious once you've done it a few times. Keep working at it and you'll get there.