Whether you're laying a mortared brick patio or loose brick, the preparation is similar. Use stakes and string to stake out the area where you want your patio. Dig up the sod with a spade, getting down to solid dirt. Level the dirt as best you can using a long level and wide, flat snow shovel. If you're going to lay loose bricks, then roll out a layer of plastic weed-blocker over the whole area; otherwise, just leave the dirt surface as it is.
To lay a loose-brick patio, spread sand over the area at a depth of 2 to 3 inches. Get it as smooth and level as you can with your snow shovel and level. Soak the sand with water from a garden hose on a light spray setting (so you don't shift the surface around). Let it dry completely, then repeat, twice. This will get the sand packed tightly. Lay your bricks gently into the sand, leaving about 1/4 inch between them. Put them in any pattern you want---staggered rows, checkerboard or a diagonal criss-cross. Spread more sand over the patio, sweep it into the cracks with a broom, and wet it down again. Once it dries, your patio is ready to use.
Spread dry mortar mix 1 inch thick throughout the area. Get it as smooth and level as you can. Lay the bricks over it, leaving about 1/2 inch between them. With your garden hose set on a light sprinkle setting, thoroughly soak the patio, letting the water seep down into the spaces between the brick. Let soak in, and wet again. Repeat this several times over next hour, then let the mortar set for two to three days. Come back grout between the bricks with more of the same mortar, using a rubber grout trowel to press it into the spaces between the bricks and squeeze it off the face of the brick. Gently hose down the brick, without gouging out the new mortar, and let it dry for a few more days before using it.