There's a piece of advice that gets repeated so often it has stopped meaning anything: shoot in the golden hour. An hour after sunrise, an hour before sunset, warm, low, flattering. It's true. It is also, for most people with a job, advice to shoot roughly never.
The hours you actually have a camera in your hand are the bad ones. Midday, flat and contrasty at the same time. A kitchen at 7pm under a single overhead bulb. An office. A bus. February.
So here's the reframe: you are not waiting for good light. You are learning what each kind of bad light is good for.
Hard midday sun
The complaint is that it's harsh, that it puts raccoon shadows under people's eyes, that it blows out. All true, and all irrelevant if you stop pointing it at faces.
Hard light is the only light that makes a clean, sharp shadow. Shadows are free graphic shapes — a railing becomes a line across a wall, a fire escape becomes a pattern, a person becomes a silhouette with a shape you couldn't have posed. The prompt the shadow, not the object exists precisely because midday is when it works and golden hour is when it doesn't.
Point away from people. Look at walls.
One overhead bulb
Terrible for faces, excellent for objects. A single hard-ish source from above gives you exactly what a studio photographer would build with one light: a top-lit subject with fall-off on every side. Put something on the table directly under it. A glass, a hand, a set of keys.
The trick is to stop trying to light the whole room. Let everything more than a foot from the bulb go black. Underexpose deliberately — a stop, maybe two, below what the meter wants — and you get an object floating in darkness instead of a badly lit kitchen.
Flat grey overcast
The one everybody calls boring. It's the best portrait light that exists and it's free — an enormous soft box covering the entire sky, no shadows to fight, no squinting. The reason it looks boring is that it's boring on landscapes, where you need the sky to do something. On a face at two metres it's perfect.
If you're outside on a grey day, shoot people. If you're outside in hard sun, shoot shadows. That's most of it.
Almost dark
Where phones now genuinely beat old cameras, and where you should stop caring about noise. Grain is not a flaw. It's the texture of the photograph, and every photographer you admire from before about 2005 has it in every frame they ever made at night.
Turn the flash off, brace against something solid, accept the blur that comes from a slow shutter, and take eight frames instead of one. One of them will be sharp enough, and the blur in the other seven is often better than sharp.
None of this is a workaround for not having the light you wanted. Bad light has its own grammar and the whole job is learning to read it — which you can only do by shooting in it, on a Tuesday, in February, when you'd rather not.