So as the manufacturers won't give you decent instructions, I suppose I shall have to do it for them.
The first thing to recognise is that Astra 2, the satellite system that carries the UK channels, isn't the only system up there and ordinary signal meters can't distinguish between them. Secondly, Astra 1 and Hotbird both punch out a stronger signal than Astra 2 does. Therefore if you simply turn the dish until you get the strongest reading on the meter, the chances are that your dish won't be pointing the right way.

The other point to make is that although a meter will sometimes react to a signal coming through trees, the digibox won't. If there are trees in the way, you won't get a picture so make sure you position the dish so that it has a clear view round or over the obstacle.

This is how to use the meter:
The meter will have 2 screw sockets on it. Use a short length of cable to connect one side of the meter to the dish and connect the other side to the digibox. There will be a symbol to indicate which socket is which. The meter won't be harmed if you get it the wrong way round, it just won't work. Now switch on the power. An electric current goes along the cable to the dish to operate the LNB and this same current also powers the meter. If the meter has an audible tone option, turn it on. You'll hear a steady buzz from the meter.

Switch on the TV and digibox and pull up the Signal Test screen (Services, 4, 6 on the remote control on a Sky box or Menu/Information on a Freesat box).

Now set the rim of the dish roughly vertical (or if it's a Multimo or Arcon type, aim it to the elevation indicated here). 'Roughly vertical' is OK for the British Isles or the Low Countries etc., but if you're further south you might have to raise the rim higher. (But don't go mad! Most dishes are of the offset kind and are not aimed directly at the satellite but some way below it so that the signal hits the dish at a downward angle.) At this stage it's a matter of trial and error.

Point the dish towards the east and then slowly turn it southwards until you hear the meter's tone begin to rise in pitch. If there's no change in the pitch and the meter has a sensitivity adjustment, turn it up to high. You should eventually detect a rise in pitch and the dish should be turned until the pitch is as high as you can get it (reduce the sensitivity if necessary). If you still don't detect any change in the pitch, you'll have to try altering the elevation a little.

Once you have a tone peak, clamp the dish horizontally and raise or lower it until the pitch reaches a new peak. Now look at the TV screen. If it says 0002 and 07d4 (Sky box) or 003b and 0802 (Freesat box), you're in business. If it doesn't (if it still shows zeros or it now shows a numeric display that isn't 0002 or 003b), then you're pointing at one of the other satellite systems, not Astra 2/Eurobird.

Remember I said that Astra 1 and Hotbird have stronger signals than Astra 2? Try turning the dish back towards the east again. (You'll need to reset the digibox first by powering it off for 30 seconds.) The tone will drop initially but should then rise again, though not as high as it was. Again adjust the elevation until the pitch is as high as it will go (see the next paragraph), and then check the screen again. With a bit of luck, you should now be looking at Astra 2 and you'll be able to back out of the Signal Test screen and return to the main screen. You will see a message saying 'Searching for listings' and then the Sky Welcome screen will appear.

If you initially hit Astra 1 or Hotbird, in addition to moving the dish eastwards to Astra 2 you will also need to lower its elevation slightly, typically by 3 degrees from Astra 1 and perhaps 4-5 degrees from Hotbird. This is because Astra 2 is further round the curvature of the earth as viewed from Europe and therefore lower in the sky.

Even with a signal meter, searching for Astra 2 can be a hit or miss affair. I personally have tried aiming my dish with and without a meter and most times I've done it faster without (taking into account the extra time needed to connect and disconnect the meter). So the moral is not to give up too quickly. If you don't get a signal first time, just persevere. Take it slowly and don't be tempted to rush things; you'll get there in the end.