To memorise many numbers and/or concepts one needs very long journeys. Rooms are most appropriate to fulfill this aim. To memorise a phone number or a shopping list for example, sometimes you only need a few points. For this purpose, it is appropriate to use something you "always keep with you", namely your own body. We choose body parts to which we mentally tag the items we need to remember.
And here is the Body Journey
If you advance in training, you will undoubtedly need multiple journeys. YOU can create them progressively on your own under "My memocamp". Another journey is the "samplehousejouney". It consists of 52 journey points allowing you to remember a whole deck of cards.