Each snap, text post and comment has a "Save" button available for other members to use to quickly save. With snaps and text posts, the Save button is just on the right side of the voting bar that shows the voting arrows and total votes. All comments have a Save button just underneath them. Clicking one of these Save buttons will load a popover which allows you to select an "edition" of where you want to place your save into. These essentially act as folders to organize all the things that interest you. Once you finish by pressing the "Save" button, the item will be added into your saved posts area.