Aviation shears are a must for close trimming. Large cuts can be done with a jig saw, power nibblers or power shears. Have plenty of replacement blades available for all tools being used.
It is a must to have ladders and, a scaffolding really comes in handy if one can be borrowed from a friend.
Work In Sections
Since you do not have to remove the main layer of old shingles you can work in sections just enough to keep the job going. That means putting down the foam, nailing down the flashing and anchor rails known as J-Trim and Reverse J-Trim by this manufacturer. These all go on top of the foam.
It is recommended to wear good leather gloves to avoid cuts from the sharp steel edges. I would also recommend sunscreen.
Most houses will not measure TRUE or SQUARE and minor adjustments have to be made as you work. The best thing is to work slow and calculating and take plenty of time before making final cuts. Following the diagram will help in deciding which length of panels to use for which cuts.
The panels will be delivered in lengths sufficient to cut all the angles needed with relative ease. Once a few pieces are cut and installed the job becomes mostly routine and repetitive. Be prepared to do a lot of nailing and driving various kinds of screws.
All of the ridges have to be run on top of the foam sheeting. This is best done in sections rather than putting the foam sheeting across the entire roof first. The foam sheeting is somewhat slippery and HOT. Foil faced sheeting that helps reflect heat is like working on a hot grill. The surface is cooler to touch than the asphalt by many degrees but the reflection is hard on your eyes as well as your skin being sunburned.