Living within my means
There are two aspects to this:
1) Living within my means economically. So I can not take on debt, lust after things I cannot have, desire more than I can obtain, or participate in runaway consumerism.
2) Living within my means of time. I cannot predict, nor participate in, the future (when “it gets here”, it will be present). Nor can I relive or recreate the past. There is only Here and Now.
In regards to #1, I have been a practicing minimalist on a tight income for the better part of a decade. I accept and endorse this, and am quite happy with where I'm at.
In regards to #2, I try my best to stay in the moment. Not making too many plans for the future, nor mourning or regretting the past.
Of the two, I think the second one is much more important. For me or for anyone (but others may do as they wish). Being happy, and healthy, and fulfilled BY living in the present moment, and embracing those moments more often, I find myself much more at ease. More contemplative and relaxed. High speed (or, living at high speed) can be exciting and thrilling and fun, with the caveat is that life, itself, is the ground being covered, the road traveled, the time lost. If time is not important, then nothing is important, because time is the only valuable thing I have.
So, staying present, and within that time, is my highest priority.