Pad Template
Inner Pad Template

Place template on the fold of the fabric and line up with the fold line on the
template, cut one. Take the same template and cut 2 pieces from the full
template. Not on a fold.  Cut about 8 pieces of fabric from the oval template.
This number depends on the thickness of the fabric. 

Here are all the pieces cut out. My oval pads are 4
layers each. This is thick double napped flannel I'm using.  

Serge around the edges of your pads and down the center
 seam of the 2 separate body pieces. This prevents fraying of
 the flannel  

Take your two separate body pieces and place them over the
whole body piece, lining up the edges.  Your two center seams
 with overlap 

Serge around the entire body.

Here's the body and the two pads. 

Add a snap or two and you're almost done. I say a snap or two
because some underwear have different crotch widths. If you
 add an extra snap you wont have extra wings hanging down
 from your underwear. 

I like to have extra protection so I take a quilted waterproof crib
 pad and cut one oval liner and serge the edges. Once I did this,
 I never ever had a leaking problem.

I put the waterproof pad in last so it's closest to the underwear.
I toss the soiled pads in a  bucket of water on top of my 
 washer to soak. At the end of  my cycle I pour the bucket into
 the washer and spin out  the water. I then do a regular wash
 and dry them in the dryer.