Welll in all technicality I would encourage you to release your first map, get as much feedback as possible, and if it really can't be saved, don't save it. Just don't take anything towards your map personally. You are making something imperfect, so there will be criticizm
Anyways, as far as sketching out maps goes, I would recommend finding a system that works for you. For example, I started to sketch maps on lined paper or blank paper, but then quickly realized that I had no idea how to scale the map.
Currently I draw out versions of my maps on graph paper, with every square being 128x128 units. For stairs or ramps, I already know that each stair is 12 units long and 8 units tall, a 3:2 run:rise ratio, so I simply draw them out and mark them with an arrow to indicate the fact that they're a stair/ramp.
I highly suggest recording units in your drawings, so when you make the map in hammer, it's not absurdly scaled.
Quick tip for scaling:
Thin doorway - 96u wide
Thick doorway - 192u wide
Thin pathway - 128u wide (I've seen some that are 96 or 64, but I like 128)
Wide path - 256u wide
In my book an area is too wide if it's open, and a player can walk 1024 units in a straight line uninterrupted. Hell, I think I might just make a personal scaling tip because I'm bored.