How can I avoid washing my hair as often, but not let it get super greasy?

My hair gets greasy pretty easily, I normally wash it every other day. However, I recently dyed my hair purple and until my mom buys shampoo again (she says she will then purchase color-safe shampoo), I'm cutting back on washing my hair. It helps to not put products in my hair too often and brush my hair after getting it wet but not washing it (to distribute the oils), but is there anything else?