First off, the dish needs to be mounted so that it has a good view of the sky due south and for 28E, east by about 28 degrees. (see where your neighbours Sky dishes are pointing) . Actually, try that first, if you have a view of someones Sky dish, point it the same direction.
Ok, you
start with the dish pointing down a bit, say 5 deg,
it doesn't matter too much, this is just your starting point.
Then using the receiver say, pick a transponder from the 28E Astra 2 list (10773H for example) and monitor the signal quality.
Then slowly swing the dish from one side to other until you get a signal, if you don't, tweak the dish elevation a bit and repeat, until you do. Eventually by trying various elevations and swinging the dish, you should eventually get a signal of some sort.
When you have got the best signal, see if you can watch BBC1. If not, scan the transponder and see what channels you get, they will probably be foreign ones.
Do a search on kingofsat, compare the channel name and frequency with what you have, to find out what satellite you just found. Then move dish accordingly.
The satellites are in an arc.
http://www.satellites.co.uk/satelli...t-motorised-systems/117335-satellite-arc.html
If using a cheap satellite finder, the principle is the same, except it will only tell you signal level, just try and get the max signal level, then use the receiver to scan to see what satellite it is.
BTW, I mostly ignore the numbers on the dish scale completely and just set the dish face by eye initially, the scale is good for just keeping a track of how far you have moved the elevation for each sweep of the dish. No more than 1 or 2 degrees at a time for the elevation adjustment.
Robbo