Your roof needs to be protected from leak by installing step flashing. It will not only prevent downward falling water, but also water that pushed up under your shingles that cause rot. How to install step flashing can be done easily without having to hire a professional. So, you can learn how to do it with some simple steps to protect your roof.
How to install step flashing can be started by cutting the step flashing at a 45 degree angle up to the point of the bend. Create a corner section by bending the flashing in half at the bend point. Set the flashing on the corner of the wall that rises up off of the roof and nail it to the boards of the wall with hammers and flashing nails. After that, you can apply sealant caulking to the flashing over the corner of the wall and across the flat surface on the roof. You need to apply the sealant wherever the next flashing section contact the corner flashing piece. Bend the second flashing at 90 degrees angle to overlap the first flashing and install it over the corner piece. Nail it to the wall with a hammer and flashing nail. Now you can install the row of your shingles over the flashing and install the next flashing over the second piece and the top of the first row shingle. You can keep alternate the flashing and the shingle rows to weave them together. Cut the section of the flashing that peaks along the plumb line when you reach the top and bend it to a peak shape, then install it as the other sections. You can continue your job by alternating the flashing and shingles on the other side.
How to install step flashing just needs to be more careful and exact to get a satisfied result.