After you add tracks to a Spotify playlist, you can rearrange them in your chosen order. Just click a track listing and drag it up or down the list — you’ll see a white line appear between the playlist tracks, which indicates where you can drop the track you’ve selected. Let go of the mouse button, and the track moves into its new slot. Easy!
You can rearrange with the drag-and-drop method only playlists you’ve created (unless you’ve subscribed to a collaborative playlist to which you have the right to edit, which is indicated with a green music note next to the play-list name). Any other playlist you subscribe to can’t be changed by anyone except their creators.
If you don’t seem to be able to rearrange your songs using this method and you’re sure it’s a playlist you’ve created, you probably clicked the top of one of the columns and sorted the tracks, perhaps inadvertently. Look for a small up or down arrow next to a column title (such as Album).
Playlists can be rearranged only if they’re displayed in their original order, so you need to reset the playlist view. Just click the column that displays the arrow until the arrow disappears and the column is reset.