To install shingles around vent pipe flashing and similar areas will require work gloves, pry bar, putty knife, roofing nails and roofing cement. For asphalt shingles, as you come across vent pipe flashing and similar areas the first step is to correctly measure the shingles area that needs to be cut down to perfectly fit around the vent pipe. Use a pair of tin snips to cut the shingles. Alternatively for other shingle types you can bend back the roofing shingles from above and the sides of vent pipe with a pry bar. Starting from below the vent pipe, as the shingles approach the vent pipe area, cut it according to the measurement you took. Then, set the vent flange or flashing in place. Flange is a flat rectangular surface that sits on the roof. Properly adjust the row of shingles and then install the vent flange on top of the row of shingles below it. The dome of flange should come under the second row of shingles above it. Turning the flange as you lower it into place will make the installation easier. Make sure that the hole of the flashing fits securely around the pipe. Insert the roofing nails on the top and sides of the flange or flashing and cover the nail heads with roofing cement. Make sure that you did not hammer nails through the shingles. Also, you must hammer the nails into the bottom edge of the flashing such that the flashing lies on top of the shingle below the vent pipe. Again, seal these nails with roofing cement. Once the flange is in place and sealed, cover it up with asphalt cement (or tar if it works better for that shingle type). So, in the end, the flange itself acts like a shingle. To make both shingles and the flange stick together apply roofing tar in between the edges. Proceed shingling in such a way that almost all of the horizontal section of the flange is under the roofing material. This will decrease the chances of flange peeling and roof leakage. Properly fit shingles and flashings around the vent pipe will make the area leak proof and watertight.