This circuit will give Bay ( & Bug in fact ) owners the "luxury" of intermittent wipers and if required wash/wipe capabilities.

First thing to do is get a switch, if you have an electric washer motor and want a wash/wipe system then a switch like this is ideal:-

Splashproof metal lever switch fitted with rubber gaiter. 
Fits 13mm dia hole. Single pole. 20A.@12v 

 If not then an ordinary on/off switch of whatever pattern you want, power rating is not that important as the switch doesn't handle any major current.
You can get them from a local shop (Hal fords or suchlike) or from here:-

Then a quick trip to a breakers yard, get the relay from any VW '82-90, part no is embossed on them, the one you're looking for is:321 955 531A,you'll obviously need some wire and terminals, these can be obtained from any autoparts outlet.
Now then, work out where and how you want the switch and fit it, then find somewhere to fix the relay, anywhere handy, but obviously out of site, will do.

  Now find the wire from terminal 53e on the switch, cut this wire {having made sure the battery is disconnected} and connest it to terminal 53m on the relay, then the other side of this wire, ie from the motor, goes to terminal 53s on the relay.

   You now need an ignition feed to the switch, the output side of the switch going to terminal J on the relay,  term 31of which goes to earth and term 15 is an ign feed ( fused the same as the wipers). Then take an ign feed to the new switch (fused of course-10 amp should do) Turn on ign and test.
Simple and cheap.
With this relay if you have electric washers (or are going to fit them) whatever sort of switch you use if you tap off of the wire from the switch and connect it to relay term T, you will have a wash wipe system.
Hopefully this, in conjunction with the diagram is easy enough to understand, and do, 
Like most things instructions always look more complicated than the reality, if you have any problems just Mail Me.

  This system is only suitable to later type bays, ie post '72, due to the earthing system of earlier units, I'm working on a system for early bays so watch this space.