@JUST A SNIPER ツ
Maps should look like up to date standards. And you can mainly see those standards by looking at new released maps, see how their designs are done, parts, flow, structure, ideas etc...
Another thing that they didn't mentioned is that, mapping a map takes weeks even months too map, even for expert mappers, this is because:
Map should be complete, this means: A proper and suitable length (this is common sense of how long a map should be you cant really have short short maps because its mainly boring and meaning low effort mapping, i dont remember the fastest map so im gonna do a wild guess and say more than 5 min map now dont make it exact 5 min because i said so xD), this includes interesting/creative parts (depending on the category of map); The map should also have a clean and up to date teeish design (You can go for a more creative design if you are good mapper and you do it decent), this also includes nice color palettes. I've seen lots of maps with different color distribution and just looks awful;
And finally all parts should be working properly, tested with friends or by people, no bugs, no skips, good flow, and good transitioning between them.
Keep in mind, it is CRUCIAL to leave room in parts/transitions for the players throughout the map. And by this i mean, depending of the map structure of your map, you should leave enough space for players to feel comfortably on playing, like moving, doing a nice throw, flying, good hammer hit lenght/height, the parts themselves shouldn't have a 5 tiles gap and then the ceiling. You can have creative tight parts, but this all depends if you are experienced mapper and know how to do it so its not annoying, you get this experience by mapping and mapping and then ask people to play it and see opinions. But it is bad habit to map tight, make things nicier for players.
Discord has a word limit xD But to summarize, you cant expect in 1 or 2 days to map, and even more if you are a beginner mapper.
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at 6pm) 
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don't start it
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