Particle Fun - Three designs

Go to Composition > Composition Settings then under Preset choose one of the HDTV presets (choose your fps) then OK.

And then in Composition select Particle 01, Particle 02 and BG layers > Right click > Transform > Fit to Comp. The only thing you need to do is to make some repositions to the camera and fit the design into the Comp window.

And repeat the steps for all designs in the project, and of course change the positions for the camera and adjusts the designs for you needs.