Identify subject and shape.
First figure out what you're going to make, and make some drawings until you have a good shape. Draw on cardstock, cardboard or index card. Cut out the design.
After you have cut out the design, flip it over so you don't see the drawn image side to check how the design works as a negative image and to fix any cuts that need to be refined. You can see any "mistakes" from this angle. Trace. Trace....trace some more.
Then begin tracing. You'll need to carefully trace 20-30 and then cut them out as carefully as you can. Stack and glue.
If you had one of those fancy machines you could use it and then presto! But alas, no fancy machine...
Begin gluing your shapes together, spreading the glue around the surface of the paper, and stacking up the shapes. You'll especially want glue near the outside edges, but you also don't want a puddle. Press the stack down occasionally to squeeze out extra glue.
Use wax paper to protect your table top and also to keep it from gluing to your table. Let dry overnight.