How do I apply bias tape to a quilt block?

I have 12x12 sqaures and am adding a diamond shape 4x4 square to the center, and wanted to add a border to that center 4x4 diamond shape. I have bought double and single sided bias tape and I am about to pull my hair out...I have no idea how to do this! No one in my family can sew and I don't know what to do to learn how to finish this quilt.