This is a fairly simple task and should take no longer than 1 hour for a novice homeowner.
Tools and Materials:
Cold chisel
Hawk
Jointing trowel
Mason's trowel
Mixing trough
Short-handled sledgehammer
Wire brush
Work gloves
Safety goggles
Mortar mix
Replacement brick
Water
Brick repairs usually consist of either replacing crumbling areas of mortar or removing and replacing a cracked or damaged brick.
The first place to look for matching brick is around your house. Check the garage, under porches etc for some left over bricks that might be laying around.
Though you'll often find replacements for damaged bricks that closely match the originals, the surrounding mortar is far more difficult to duplicate. Add powdered colorant, if necessary, to match the existing mortar. Typically, it's necessary to test a few batches before finding one that will blend with the rest of the house. Always wait for the mortar mix to dry before comparing it to the original mortar, as its color may change in the drying process.
The first step in replacing a broken brick is to chisel it--and the surrounding mortar--out of the wall. After cleaning out the hole and spritzing it with water, spread mortar on the bottom of the new brick. Then spread mortar on its top and sides, and slide it into place.
1. Remove the Damaged Brick
Wear safety goggles and work gloves for this step. Working from the joints in, use a cold chisel and heavy hammer to chip away the damaged brick.
2. Clear the Surrounding Area
Break away remaining chunks of mortar, and then wire-brush and sweep out debris in the surrounding area.
3. Coat the Brick with Mortar
Mix enough mortar to thoroughly coat the mating surfaces of the replacement brick, a process called "buttering."
4. Fill the Joints
Force more mortar into the joints as needed (some will likely fall off), and then tool the seams to blend in the repair.