Looping videos without any noticeable sign of a start or end adds so much production value to your work. The cool thing is this technique only requires Photoshop and is so simple you'll be kicking yourself for not knowing how.
Have you ever spent five minutes watching a video on Instagram only to realize it was on a loop? Maybe that's just me, but I must have wasted hours of my life being fooled by well-executed clips! Seeing the jolt of a video restarting defies the objective of making work look like it's infinitely playing. The illusion is instantly broken, which seems a shame to spoil all that hard work with such a minor detail. Russell Brown, a senior creative director at Adobe Systems, has made this useful video tutorial so you will never see the join in your loops again.
Using a time-lapse made with his iPhone, Brown drops the footage into Photoshop, where it appears in the Timeline. He goes on to explain how you borrow two seconds from the start of your sequence and place it at the end of your timeline. This two-second clip is now faded into the original using a transition, and as a result, the final video appears to be infinite.

Obviously, everyone’s footage will be different, so I would play about with the length of the clips you are using to transition.
Looping videos without any noticeable sign of a start or end adds so much production value to your work. The cool thing is this technique only requires Photoshop, and if done right, you won't see any repetition.
Just like the first and last paragraph of this article.
[via ISO1200]