Brand, thing, behavior, method, advice, mantra, etc.
I swear by Blackwing pencils.
Also, the 'two minute rule', which has really improved my life: "if it takes two minutes or less to do, just do it now; if it takes longer, schedule it." I've got untreated attention issues and it's very easy for me to notice something needing done, and overlook or procrastinate it because it seems inconvenient in the moment. Having a totally painless rule that forces me to acknowledge that thing I should pick up, that trash bag I should change, etc, or, to at least put on my calendar anything I mustn't forget in the long run has been great for me.