Its a little late in the season to make soil (compost) from scratch. Usually you take your grass clippings, leaves, and table scrapes. Put them in a large container, add some compost starter, and mix every few days. After about 2-3 months you should have fresh dark composted earth.
A quick and cheap replacement to compost is to head over to your local garden or hardware store. Look at each of the premium soils they have and inspect the ingredients. The bags that feel like wood chips and ground up bark is best for outside. The bark takes several seasons to decompose. Where as a lighter mix, made of peat moss or coir is better for seedlings and small container plants. The exception is when you use fabric pots. The fabric allows so much air to pass through that you want a heaver soil to absorb and lock in the moisture.