You ever take off any plans before?
Or have you had to sit down and order the material for a job trying your darnedest not to forget anything but also not buy too much? A wee bit of extra being better than not quite enough? Then take the crew out and install said material in as efficient a manner as possible?
If that was your job for long enough you should know what it takes in both time and material to get each phase of a house wired.
Get pricing, pray it doesn't go up too much next week if you don't have the money or the storage space to buy it all up front, and add it all up.
If you have employees you'll have to figure out what each one REALLY costs you per hour to get your average man/hour rate. If it's just you use your best guess of what your competitions REAL M/H rate is.
Add to the total a small percentage for overhead (unless you have huge overhead for some reason) and a certain percentage for profit (cause that's what the other guys are going to do).
When your done your number should be have you making and not losing money. Better to lose the job that do it for almost free. But you shouldn't be leaving too much on the table every time either and short of CGs or competitors actually telling you where you should be the only way to find out is to lose one now and again.
Comb over every page and every note of the plans. Something missed in the plumbers notes like an instant hot water dispenser will take a circuit for sure.
When the architect draws the condensing unit 10 feet from the panel don't believe it. Include enough wire to hit the farthest corner of the building.
Same with the service. Unless you have it on VERY good authority that it will be where its shown figure your home runs and bonding wire for worst case.
Ask a LOT of questions. Septic pump? Where? Well? Where?
Future pool/outbuilding? Where? Yard lighting, gate power, etc....
Now the tricky part is seeing in 2D that that gluelam is going to add X # of feet to the home runs or even cause you to add a sub to keep length down......or that something is being speced that you've never heard of and no idea how to set up for.
That should get you started and you might even prefer it to software although I'd bet the software would be helpful for areas where your hands on is limited.
I wouldn't try to bid too far out of my direct experience but should I push my envelope a bit I will be trying some software.
A GC that I used to labor for many years ago once said about the subject of bidding "You sit down to the plans and your scared. You try to think but you can't, because your busy. Being scared."
Don't forget the t&m for underground, the riser,the service and ALL of the breakers. I did that on one of my first bids and ate that on 2 copies of that house. Oops.