I’ll be in London for about a week soon and travelling around by public transport. I don’t fully understand how Oyster works, or feel comfortable using it. Do I literally just tap in and out and on and off and the cap will just be equivalent to buying a weekly travelcard? What happens if I forget to tap it (I’ve done this before and had a fine). Would it be better or even possible for me just to buy a travelcard? I do have an Oyster card but I usually only use that for day trips. Help me oh hive mind.