Lets start with the basics first, the walls against the concrete want to be away from the concrete (not touching) and the space behind the wall at the top where you can see floor joists and things, should be blocked or filled or covered with would plywood, or drywall to give it a 30 min. fire stop. At the top, you decide how far out you want to build your wall. measure out from your sill plate at each end of the wall and put a line accross with a chalk line. If you are running with the joists install a block between them every 2 or 3 ft. Block are usually 10.5" or 14.5" pcs of 2x4.
If your wall is out about 16" and your sill plate is back on the concrete say 4" put up a 20inch wide peice of drywall so that it touches the sill plate but dosn't quit hide your line.
This the same program for the walls closer the the concrete. Now you can nail up the top plates of your walls all around the room. With a straight 2x4 and a level you can transfer the marks to the floor. When installing the bottom plate be sure to protect it with plastic or tar paper or sill gasket. You can nail it down with 2" concrete nails but better if you have a hammer drill. Drill 3/16" holes and with a peice of rebar tie wire and a 3" nail you can really nail it down. Where 2 plates meat in the corner, mark out for 2 studs one for each wall, they will be kitty corner to each other. From the conrete side of these studs measure out 15 1/4 or 23 1/4 and tack a nail there. You can now hook a tape measure to that and lay out your floor plate at 16, 32, 48, or 24, 48, 72. match whatever you do on the top plate.
Now for your cupboard. We usually leave out the bottom plate in this area and build a box out of 2x6 and put plywood on top of that and just set it in place for now. Don't for get the plastic. The walls for the cupboard will sit on top of this box. Pick a height for the top of your cupboard from the floor and and cut two studs that high. They are criple studs one for each side of the box and install a full height stud on the outside of each of them. Build a 2 ply header from 2x6 3 inches longer than the box and it goes ontop of the criples. Add studs above to the top plate and a 2x4 on flat under the header. Build a the back wall the same length as the box and a few inches higher than the opening and build the side walls to side in. Of corse you will figure all this out and put the cupboard walls in before you install the headers.
Just in case you think I forgot in the corners where everyone puts the extra studs we just put in junks of 2x4 to tie the 2 walls together. Don't forget about insulation and vapour barrier.
When your doing the fire stop keep in mind that this area does need some access to outside air. It must be vented.
I hope this helps and welcome.
