Come to the top end of town (opposite end to beach), at roundabout (which was old Dolphin roundabout), turn left and walk alongside the dual carriageway.
Cross over the road towards the "canal" and walk along this for 10 mins until you come to a concrete bridge that dips like a U. cross over the bridge so that "canal" is on your right and keep walking. Lapis is a couple of minutes up on the left.
There are other routes to walk along the main road but this is the most straightforward way to explain for now. Hope it makes sense!