This puzzle is in six parts. The final puzzle is a meta-puzzle which requires the answers to the previous five puzzles. If you have trouble with one of the first five puzzles, try skipping it and coming back to it later. You may be able to solve the final puzzle even if you do not solve all of the first five puzzles.
When viewing on a touch-enabled device such as a phone or tablet, swipe the puzzle to the side to advance to the next or previous puzzle. When viewing on a non-touch-enabled screen, click the arrows at the edges of the puzzle to advance.
More puzzles are available here.