TRAINERS:
If you would like to catch a pokemon, battle them. Pokeballs are unlimited here, as there is no pokemart. Leave the desired pokemon with 5 hp or less. Throw the pokeball. The pokemon may choose if they would like to be captured. Pokemon may come up to you and ask you to be their trainers. You may accept or decline.
POKEMON:
If you are being caught by a trainer, you have the option. You can let yourself be caught, or escape from the pokeball. You may run from a battle. Do not run away repeatedly, unless you want to live as a wild pokemon, in which case, type in parenthesis to the trainer who wants to catch you that you do not wish to be caught.