Newbie Fate GM here, I will soon GM my first ever session. Seeing how important being aware of all aspects at play at any given scene is, how do you keep track and announce all the various aspects currently at play? Do you use post-its? Hand out sheets of paper? Enumerate loudly and have players write them down? I feel I may lose track of all the aspects at play, and my players too...
Index cards are the canonical tool (what the book suggests). It's not the only way.
They're easy to pick up and get rid of when one of them stops being relevant (the scene changes, someone Overcomes the Aspect and it goes away, etc).
I label them with "Scene Aspect", "World Aspect", or what-have-you. Some people use color-coded cards for that. For an Aspect on a character, something temporary, created by an Advantage action or something else, I typically still use an index card (labelled "Advantage") and clip it to my copy of the character sheet (instead of writing it on their sheet, since it's temporary: usually lasting for the scene, definitely less-than-a-session).
You can do this with post-its instead, or with a list on lined paper, or with some digital tool. They would all basically work the same way.
What I lose track of more frequently than the actual Aspects are the free-invokes which may have been gained on them, and whether they have been used up or not. So I put squares on the index cards and check them off as the free-invokes get used.
I also actively coach players to not-forget that there are Aspects on the table and that they should maintain some amount of awareness of them. Or, more precisely, their characters should (in-character situational awareness). One way I do this is to repeatedly refer to them in my GM patter. Another is with out-of-character nudges.
I actually prefer Post-It notes to index cards when I play FATE in person. Post-It Notes and some way of tracking FATE points and free invokes, like M&Ms or spare dice that I might have left over from some other game we're not playing at the moment. When you're playing in person, this has the added bonus that everyone sees you scribbling a Post-It out and slapping it on the table so there's no confusion as to whether or not they can use it.
The advantage of them, I think, is that index cards just seem more, I don't know, permanent. Nobody cares if you crumple up a Post-It when it no longer applies, but you actually have to collect and pile up those index cards (and I do actually use these myself, but generally when I'm making fractals rather than situational aspects).
I play on roll20, so my advice may not fit for your table, but I create lots of little tokens and tags and objects for people to actually see.
The one time I've played it in person I used note-cards and just jotted stuff down and set them out on the table for people to see.