Looping a motion graphic background

[Shelby356401498xz8]

Hi! I'm wondering if anyone can help me to loop this background where it doesn't show it starting & ending. I'm new to after effects & I'm trying to make motion graphic backgrounds for my church. With it showing where it starts and ends, it won't look that great. I've looked up many tutorials but I feel like none of them are really all that helpful. Thank you for all your help in advance! 

Attached is the video of my design. 

[Mylenium]

Not possible. It's way too short to do anything with it since it doesn't even start and end at the same frame. You would have to rebuild it from scratch for a seamless loop. Everything else is going to lock bad one way or the other.

Mylenium

[Shelby356401498xz8]

And if I made it longer, how would I get it to start and end with the same frame?