Sorry, I don't have more pics available right this minute.
Basically you're setting the pickets side by side to make the top of the pallet. Select the pieces you want, that look the best. That's what you'll see from the top. All done? Now, turn the pickets over to the other side. Cut the 2x2 pieces into lengths that match the width of your pallet. Lay them on the back side, across the pickets. Nail or screw them in, two or three nails/screws per each picket. Now, flip it back over. The pickets you selected will be on top. The "feet" will be on the bottom, holding the pickets in place, and keeping the pallet off the ground or other surface.
Visualize a section of a picket fence. The smooth side is the top of your pallet. The back side held together with the cross pieces is the bottom of your pallet.