What are the two main ways in which a hormone might affect a target cell?

Answer 1

Hormones activate a cell as an ON switch, just as in case of sex hormones affecting a follicle, in order for it to start growing pubic hair.
Hormones can also signal a group of cells into a path in organogenesis just as in case of embryos, they move according to hormonal signals. This movement leads to organogenesis.

Answer 2

A hormone affects the cell either via cell surface receptor or trigger secondary messenger cascades (ex. cAMP) to elicit different responses to the human physiology depending on which hormone is in question.