Here is the front pack crisscrossed through the fork of a Western or Endurance saddle.  If you have an English saddle that has a pommel you will use those straps and attach your pack to the breast Dee's on the side of your saddle

Video of front pack attachment for Western, English and Endurance

Here is how you will keep the sides of the front pack secure and bounce free. You will pull tight the side strap securing your load.

Here is how the side strap will look under the skirt/flap of your saddle.  The side straps are VERY long so you will be able to reach rear part of your saddle enabling you to find a ring to thread the strap through.  There is even a plastic D with a tie string on the slime-line pouch that you can also use to secure the pommel bag. Tie the string on to the closest Dee or ring nearest the pouch. 

Then you are good to go!