Brick 'em up
Having already done a doorway, I'm getting reasonably proficient at this bricking up malarkey. It's just a case of taking out a few half bricks at the side to improve bonding into the existing brickwork. I use one of these seriously-handy heavy-duty 4kg hammer drills (see side link). Then mixing up a 5 to 1 mortar mix with some mortar additive to make it workable (very important). Soak your bricks briefly in water - this makes for a stronger bond. Then lay carefully, being sure to get them level on all planes. I lay on a peaked bed of mortar, which allows you to tap down into position without filling the cavity (and your boots) with excess mortar. Tap them along sideways too to get a good squish on the end joints and then check the face of the brick is upright and not recessed or protruding and that the brick is running level with the existing and not high at one end or the other.
Getting the mortar bed right is the secret. Too much and you just won't get the brick level. Too little and you've got no adjustment.
When you get to your last course of bricks, let them set for an hour or so before trying to fill the final gap with mortar. Then put some mortar on scrap piece of wood (say 10mm ply) and hold it against your last course, level with the gap. With your trowel push the mortar off the wood into the gap, the ram it home with another thin piece of wood. If you don't let your last course go off a bit, you'll find these bricks will start to move around. That's my advice, anyway...
Heavy-duty hammer drill saves much time
