There is a strange gap in video tooling right now. Enormous effort has gone into models that generate footage from nothing, and almost none into the thing most people actually need: they already have the photos and clips, and assembling them into something worth posting still takes an afternoon.
Assembly is the boring part. It is also the part that eats the time.
What assembly actually involves
Writing a script that fits the footage you have rather than the footage you wish you had. Recording or generating a voiceover and timing it to the cuts. Choosing which clip covers which line. Adding captions, because most people watch muted. Exporting at the right aspect ratio for wherever it is going.
Each step is simple. Doing all five, for a sixty-second video, is a couple of hours the first time and about forty minutes once you have a routine.
The order that works
Script first, always. Not because the words matter most, but because the script determines how many shots you need and how long each has to hold. Writing the script after you have cut the footage means rewriting to fit, which is slower than it sounds.
Then keywords, which is a step people skip. If you tag what each section is about, matching footage to lines stops being a memory exercise and becomes a lookup.
Then voice, then subtitles, then export. Subtitles last, because they have to match the final audio timing, and any earlier change invalidates them.
Pick the aspect ratio before you start, not after
A 16:9 video cropped to 9:16 loses the sides of every frame, which is exactly where people usually put the subject. Vertical footage stretched to landscape gets pillarboxed and looks like a mistake.
Decide where the video is going first. If the answer is everywhere, shoot and assemble vertical — a 9:16 video posted to a landscape feed looks intentional far more often than the reverse.
On captions
Burned-in captions rather than platform captions, if you have the choice. Platform captions get switched off, render inconsistently across apps, and disappear entirely when someone downloads and reposts your video.
Keep them to two lines. Three-line captions cover the subject on a phone screen, and the third line is almost always a word or two that would have fitted above.
The honest limits
This approach does not invent footage. If you have nothing to work with, no amount of assembly helps, and that is a genuinely different problem requiring a genuinely different tool.
It also will not save a video whose script does not work. The pacing of an assembled video is set by the writing, and no amount of cutting rescues a weak first line. Spend the extra ten minutes there rather than on transitions.