You can read a blog on Sinti Monastery on our main Paphos Life site. Guest written by Max (see related pages links further down page), it shows a route which is currently closed due to flooding. If you want to visit now, you will have to come from the direction of Pentalia. It is well worth the journey though, the rains have scrubbed the monastery up nicely, and the grey clouds provide a suitably gothic backdrop to your visit. The tour also takes you to the Xeros River itself, though there is an accompanying film which shows that off better.
Please note, when you visit the monastery, you may be apprehensive about wandering around. Don't be. Nobody lives there now, and you will not be disturbing anybody. You are allowed to look around and appreciate the surroundings at your leisure.