Use a measuring tape to measure the desired width of your set of stairs. The stairs should be at least as wide as the sliding door, preferably with three or more inches of extra space on either side of the door frame. Use colored chalk or spray paint to mark the sides of the steps on the ground.
Measure the distance from the ground to the base of the sliding door and divide by six inches. Each step will be composed of two layers of bricks approximately six-inches thick in total. Use 10½ inches for the depth of each step, which is the approximate width of three bricks, and multiply by your number of steps to determine the total length of the set of stairs.
Use your measuring tape and chalk dust to mark the outline of the entire set of steps and dig out a trench inside the marked area to a depth of eight to ten inches.
Fill the trench with concrete and allow it to set completely according to the directions. The concrete will serve as a solid, level foundation for your outdoor stairs.
Spread a layer of mortar ½-inch thick on top of the concrete using a trowel. Lay your first brick lengthwise on top of the mortar, pressing it up against the wall beneath the sliding door and aligning the outside edge with the edge of the concrete foundation. Press the brick gently into the mortar.
Lay your second brick lengthwise next to the first leaving a ½-inch gap between the bricks and pressing it gently into the mortar. Lay a level between the two bricks and tap them gently with a rubber mallet if adjustments are necessary for them to sit level. Continue laying bricks in this fashion until you reach the opposite end of the concrete foundation.
Cut several bricks evenly in half using a tile saw and set them aside. Use one of the halved bricks to begin the second row of bricks and place it ½-inch in front of the first brick you laid with its outside edge even with the edge of the concrete. Lay a whole brick next to the halved brick and continue using whole bricks until you reach the opposite end of the concrete foundation.
Continue laying bricks in this manner until you cover the entire surface of the concrete foundation. Alternate between beginning a row with a whole or half brick so the bricks in one row are centered over the joint between two adjacent bricks in the next row. This is called a running bond pattern.
Fill a mortar bag with mortar and squeeze it into the gaps between the bricks in the first layer. Apply a ½-inch layer of mortar on top of the first layer of bricks and follow the procedure used earlier to build up the step. Begin with a half brick on top of the whole brick in the first layer and continue to stagger the following rows.
Spread a ½-inch layer of mortar on top of the second layer of brick across the entire bricked area excluding the last three rows at the front. These bricks will form your first step. Follow the procedure above to install two layers of bricks and fill the gaps between them with mortar.
Continue building up your steps, decreasing your work area by three rows after every two layers of brick. The final step should fall just below or about level with the bottom of the sliding door.
Use a stiff brush to smooth away any excess mortar and allow the mortar to set for a full 72 hours before using your new set of outdoor steps.