Sow the seeds outside after the temperatures have warmed to at least 70 degrees Fahrenheit. Acorn squash seeds germinate the fastest at 95 degrees.
Bury the seeds under 1 inch of soil on raised mounds of dirt about 3 feet in diameter. These mounds warm up faster than the flat soil and provide good drainage for the plants.
Water the seeds after planting, being careful not to wash away the soil. Continue watering as necessary to keep the soil damp until the seeds sprout in about a week.
Thin plants as they come up so that there are two plants per hill or one plant every 18 inches if you are using rows. Cut the stems of the unwanted seedlings instead of pulling them up and possibly disrupting the roots of the other plants.
Save the fruit of the acorn squash plant when their skins are no longer glossy and you cannot pierce the skin with your fingernail. The seeds of these fruits will be the start of the next crop of acorn squash the following growing season.