All these methods require more than one person. I have a crude and unfortunately not very effective method for a single person to make a choice with 2..N choices available (for small values of n anyway). Though not a good method, it is better than none.

The way I do it is thus; first I hold up a hand showing the N fingers (you may already spot a limitation with my system).

Now choose one randomly.

Before you all shout, "Charlatan", stop. This is just the seed value.

Now you need a nursery rhyme, some song lyrics or something similar. Sing or speak your song/rhyme, while counting through your fingers. Count a finger per each syllable or maybe word but take care not to count on each beat - this is rather predictable and will ruin an already poor algorithm.

When you reach the end of your little sing-song you will have made your decision.