First you have to cut the particle board to specifications and then put a build-up strip underneath the edges with glue and use 1¼” nails or screws to attach it.  Then you belt-sand the edges smooth being careful not to tilt the sander when doing so.  I usually use an orbital sander to get inside corners.  Then you attach the counter top with screws, countersinking the holes beforehand so the screws lie flush to the surface.  If screwing the surface is a problem, you attach it with construction adhesive and let it dry overnight.  You then cut your laminate to size with a router.  If the piece is lengthy, you must have or make a bench long enough to cut it using a straight-edge as a guide.  To cut the 1½” strip, I personally have a tool that cuts strips of laminate within seconds.  You then apply contact cement to your edges and the strips of laminate.  Usually a period of twenty minutes will suffice before attaching strips to edge.  You then router the top and lastly belt sand it smooth (with no less than 100 grit sandpaper) and blow away any dust present.  You then apply the adhesive to the counter-top and do the same to your sheet of laminate and let it dry accordingly.  (I like to call it laminate because that’s what it is; Formica is just a brand name).  You can use cardboard strips to place the laminate before sticking it, but I prefer using Venetian slats because they are bowed and provide adequate height separating the two surfaces of adhesive.  You then remove the slats one at a time and press the laminate to the counter-top.  I apply some Vaseline to the edge of the counter before cutting using a three-fluted router-bit, but a two fluted is okay too.  Some people apply a strip of masking tape instead; but there is more to file in the end.  I use acetone to clean up the adhesive vs. thinner because it beads up instead of thinning the adhesive which could somehow leak into the bonded surfaces.  Not good.  Of course you cut out the sink hole, being careful to take exact measurements, because –like cutting the laminate- it is a one-shot deal.  And of course you lastly file the edges carefully with a laminate file.  A little trick cutting in corners (because the trim-router only reaches so far), is to use a metal straight-edge and score it with a razor-knife and carefully wiggle the piece off, and take care filing this area.  The end result is:  a customer who has something “that will last a lifetime” all for the measly price of what we carpenters (vs. electricians and plumbers), charge.  Sy