For beans to grow successfully, the site you need for planting should be in full-sun, in well-drained and fertile soil. It also helps if the soil is crumbly (friable). Pinto beans also require a long growing season, with a dry fall, to ensure good quality beans, so this may be a consideration, depending on the climate where you live.
You can start germinating your beans indoors, before you plant them outside, or plant them directly into the ground if you live in a warm climate. To start germination indoors, put your beans onto some damp kitchen roll, and into a warm and dark place (like an airing cupboard) for 3-4 days; you should then see germination taking place.
Late spring is the ideal time to start planting your pinto beans, well after the threat of frost is over, and the soil is warm. You only need plant your seed 1 inch into the ground, or further down (1 1/2 inches) if it is light, sandy soil. Each bean should be planted 2-4 inches apart, and in rows that are 2-3 feet apart - hence the need for a large area of space for planting.
To help germination, keep the top of the soil from becoming crusty with the use of sand or peat. You may also find germination is helped with the use of a saltpeter solution, which is often helpful in softening the outer shell to make germination easier.