I have started creating play lists on u tube by using the "add" function on screen and this works perfectly well, however I have added a couple of tracks by mistake and cannot see how to remove them.
It's a bit convoluted! First, click on your user name, top right of the YouTube screen. That should bring up a box at the top with your playlists in. Then click "View list" of the one you want to edit. Then click "Edit playlist". You should then be able to tick the ones you want to delete and select Actions > Remove videos from playlist. Repeat for other playlists as required.