Installing base cabinets. A built-in look with pre-fabricated cabinets might seem to call for tricky carpentry. Not so! The cabinet manufacturer has done most of the work, providing you with perfectly square modules that you can interlock with screws or dowels. Assembly consists of leveling and plumbing each cabinet, then fastening it to the wall and it's neighboring units.
Use the screws specified by the manufacturer, and drive in screws through frames rather than the thinner back and side panels. If a baseboard, door, or window casing gets in the way, remove it carefully, trim to fit after the cabinets are in place, and reinstall.
Install the countertop by screwing angle brackets to the counter's underside and to the cabinet frame. To hang heavy wall cabinets without help, build a temporary, movable support you can set on the counter or floor. Rest a unit on the support, shim behind the cabinet to plumb it, then screw through the cabinet frame and shim into the wall studs. Finish off the job by installing filler strips or molding to cover any gaps between the cabinets and walls or floor.
Installing the base cabinets. Mark the
location of the wall studs. Then mark a
level line at the height of the base
cabinets at the highest point of the
room's floor. Next, set a base cabinet in
place and level it to your line by tapping
shims under low points. Level from front
to back as well as side to side. Then drill
pilot holes and drive screws through the
cabinet framing into the studs. A
screwdriver attachment on a cordless
drill speeds this job along.
Once a unit has been leveled and secured,
chisel away any shims that protrude.
You're ready to install the next cabinet.
Sometimes a thin shim will compensate for
minor irregularities. Face edges must butt
together, though. Fasten units together by clamping face frames together, drilling pilot holes, and driving in two screws into adjacent cabinet doorways (with the cabinet doors removed, of course).
Installing kitchen wall cabinets. The biggest problem with hanging wall cabinets is lifting their weight to the required height. You'll find it invaluable to have a helper hold the cabinets in place while you drill and fasten them to the wall studs. Remove the door and any wall shelves before hoisting the cabinets into place to lighten the load and also provide a surface for your "C- clamps" to hold units together. Also, it's easier to work on wall cabinets if you hang them before installing any base cabinets beneath them.

Cap off base cabinets with a cabinet from a home center or a kitchen supplier. Most dealers will cut one to size and even make a cutout for the sink if you supply a pattern.
Measure carefully; because countertop mistakes are expensive. You can also make your own by veneering exterior-grade plywood with plastic laminate.
How To Install Kitchen Cabinets
In A Hour.com

Find stud locations with a stud finder. Snap vertical chalk lines to indicate either the stud centers or the stud edges. Measure up 54 inches-the standard height of wall cabinets-from the floor at both ends of the wall and snap a horizontal chalk line.
Starting in the corner with the highest floor point, nail up a temporary 1x3 so it's level; it may not match the chalk line if the floor is not level. Place a corner or end cabinet on the 1x3; check level. Drill 3/16-inch pilot holes and drive in 2 1/2-inch roundhead screws in the top hanging strip into studs. Position the next cabinet on the ledger snug to the first one. Drill pilot holes and fasten the top hanging strip with 2 1/2-inch roundhead screws.
Clamp together face frames of adjacent cabinets. Drill counter-bored holes through one face frame. Fasten frames with 2 1/2-inch drywall screws. At the wall juncture, fit a filler strip to the remaining gap. Screw the filler strip to the face frame of the last cabinet as in the previous step. Remove the temporary 1x3 strip. Using a level, plumb the cabinet fronts by shimming between the wall and the bottom hanging strip at stud locations.
Drill 3/16-inch pilot holes and fasten the bottom hanging strip with 2 1/2-inch roundhead screws into the studs. Trim the shims with a utility knife. Apply trim molding to the backs of the cabinets and the wall. Stain or paint the trim to match the cabinets. Cut a valance board to fit any gap over the sink. Drill countersunk pilot holes and screw through adjacent face frames into the valence.