I would not suggest trying to hand dig in a system for a 10,000 square foot lawn. You would be at it for many many months.
You should probably do some more reading regarding system design. There are a few books out there at the DIY box stores, and the irrigation tutorial website mentioned above.
If you are installing a second meter, ask for a 3/4" meter to be plumbed with 1" Copper Pipe to your Back Flow Prevention device. This should be able to provide you with enough flow and pressure to design an efficient system for a yard your size. If you want to step it up to 1 1/4" copper pipe, you would have more than enough for sure. There is no need for anything larger than a 3/4" meter, no matter what the supply size up to 2".
The plumber will need install everything up to the output of the backflow prevention device. Basically you will start at a 1" female threaded fitting.
Once you have determined the PSI and gallons per minute available from that point, layout your zones using the combined gallon per min output of the heads not to exceed your available supply. You then Run a main supply line to your valve assembly and branch off to your zone runs from there.
With a 10,000 SF yard, you might run a main line to two or three different valve boxes depending on your situation. If you are a beginner at plumbing, I would suggest renting a small walk behind trencher to do all your digging. This will allow you some wiggle room in your connections, rather than try to learn how to use a vibratory plow.
Your ditches will be at least 8" deep, likely 12. You have to figure in the depth of the sprinkler heads, plus a connection of some sort to the pipe, plus the height of the pipe.
I would suggest a lot of research before attempting a system of this size. You are going to be investing a large amount of time and money, and making sure it is done right is going to be well worth the extra effort up front.