Off hand I'd say you did the same thing we did our first try. You followed the paved road on up the hill into the villa area. After the gate shortly in from the main road (left turn here) you need to angle off onto the sand/rock/pothole road that heads straight toward the beach. It may look nasty but go slow and you will not get stuck. When you arrive at the bar parking lot watch for signs that may say customer parkiing only. At times it may be necessary to park just a tad back the way you came in. The trail starts within feet of the north end of the parking lot. Going in on the north entrance saves the effort of slogging thru the sand from the south end. It is amazing, for as small as Friar's beach is, how far a drive it is from the south entrance to the north entrance. If by-chance you pass tennis/basketball courts on your left, main road, you have gone to far towards Grand Case.
Say hi to Danny, buy a lunch or two from him.