Designed Vocabulary Context. Use a limited vocabulary, chosen to match the set of tasks. Variety in expression may be a valid goal in some forms of writing, but it is not helpful in appliances. Pick particular words to refer to concepts, and use them consistently. Minimize Expected Path Length Context.
Many options are available.
Sequential interaction Resolution. Consider what operations are most common, and describe them first. This prevents people from having to listen to rarely chosen options before hearing the one they're most likely to want. If an option's frequency justifies it, you might provide special shortcuts for it. Describe Then Prescribe Context.