With Alicorn's permission, I'm resurrecting this thread.
I am beginning to suspect that it is surprisingly common for intelligent, competent adults to somehow make it through the world for a few decades while missing some ordinary skill, like mailing a physical letter, folding a fitted sheet, depositing a check, or reading a bus schedule. Since these tasks are often presented atomically - or, worse, embedded implicitly into other instructions - and it is often possible to get around the need for them, this ignorance is not self-correcting. One can Google "how to deposit a check" and similar phrases, but the sorts of instructions that crop up are often misleading, rely on entangled and potentially similarly-deficient knowledge to be understandable, or are not so much instructions as they are tips and tricks and warnings for people who already know the basic procedure. Asking other people is more effective because they can respond to requests for clarification (and physically pointing at stuff is useful too), but embarrassing, since lacking these skills as an adult is stigmatized. (They are rarely even considered skills by people who have had them for a while.)
This seems like a bad situation. And - if I am correct and gaps like these are common - then it is something of a collective action problem to handle gap-filling without undue social drama. Supposedly, we're good at collective action problems, us rationalists, right? So I propose a thread for the purpose here, with the stipulation that all replies to gap announcements are to be constructive attempts at conveying the relevant procedural knowledge. No asking "how did you manage to be X years old without knowing that?" - if the gap-haver wishes to volunteer the information, that is fine, but asking is to be considered poor form.
I'll start off with one of my own: What kinds of exercise can I do at home (I do have 5- and 20-pound weights), and what are good ways to get motivation to do so regularly?
Get a hair trimmer.
Set the distance to the longest setting. Cut the hair on top of your head. You might have to make several passes to get all the hairs. Use a mirror.
Set the distance to the middle setting (halfway between longest and shortest). Cut the hair on the sides and back of your head. Cut by placing the cutting part at the bottom of your hair pointing up and moving it upwards. When the trimmer approaches the top of your head (where you already cut), lift it gradually so that you get a smooth transition from middle to long length hair. Use two more or less parallel mirrors, eg the two mirrored doors of a bathroom cabinet.
Remove the distance part from the trimmer entirely. Cut the hairs on the back of your neck. Again use an upwards movement with the trimmer. Make sure that the top of what you cut is a straight line. Forming the straight line at the bottom of your hair is the point of this step.
Put the distance part back on and set it to the shortest setting. Do your sideburns and bottom of the back of your head. Start lifting the trimmer to transition almost immediately on the backside and just above your ear on the sides. Cut the hair behind your ears by running the trimmer backwards along the top of your ear, with the lower edge pressed against the ear base and the upper edge in the air.
Shower/rinse off the cut hair. Take a last pass with the trimmer or a pair of scissors on any hairs you may have missed.
This is basically how I cut my hair too.