Step 7: Job done, wait for a rain storm for results.
I only replaced three shingles for this job, plus used roofing cement under a few more that were cracked.
Step 6: Install new tarpaper
This photo shows me sliding new 30# tarpaper under the existing tarpaper. You want to install new tarpaper as far up the roof as possible, under the area where the new shingles will be placed. The 30# stuff is stiff enough to do this, 15# may not work.