The best way is using a router with a guide and a side cutting bit at high speed to minimize chipping of the laminate.
If you are going to use a jig saw, use a fine tooth blade for the same reason. For the sink cutout, first drill at the corners with a bit that matches the radius of the corner, then cut the straight runs. For the notches, just go slow to get a truly good edge.
Use masking or painters tape (2" min.) on the good side of the cuts to protect the finish and prevent scratches and marring of the laminate.
I wouldn't use a sawsall or circular saw, too much chipping and danger of damage.