One of the most common mistakes artists make when aging characters is they keep the face shape the same and just draw on a bunch of wrinkle lines. It always looks kind of wrong, in the same way as how "old person makeup" on young film stars always doesn't quite look like an actual old person.
I've found actually that changing the shape of the overall face, especially the nose and jawline, is the big key thing.
Quick and dirty sketch (probably VERY wonky because I didn't flip it lol) but...
So one key thing is that the skin around the jaw starts to droop. This tends to have a softening and broadening effect to the jawline, and also the chin may appear more prominent on some people as the rest of the jawline sags a bit around it. The exception is on VERY thin older people, where the jawbone kind of starts to look shrink-wrapped.
The eyes don't get smaller exactly, but the eyelid and skin around the eye sags a bit over them, leading to a sort of hooded and more narrow look. This is a good thing to keep in mind if you want an aged version of an existing character to remain recognisable; try to keep the same eye shape, just lower the top lid's resting position a bit.
Your nose and ears aren't bone, but cartilage, so they actually keep growing throughout your life. Older people tend to have larger noses and ears, so making the nose and ears more prominent is a good way to show age.
Try to keep wrinkles to a few effective ones that define the volumes of the face rather than trying to ink in every last line if you're drawing in a simple style, otherwise the character will look out of place with the detail level of the comic.