Being a paranoid software developer who specialises in information security, my advice is as follows...
If you are going to use a cash machine, before use...
1) Pull on the fascia, card slot and keypad bezels to make sure they aren't loose, or that any strange devices are stuck on (which could be card skimmers and/or cameras).
2) Look into and around the card slot for anything strange.
3) Look up towards the top of the machine (where the light usually is) to see if there are any small windows / holes that a camera could be hidden in. Look how small the cameras on mobile phones are... it doesn't take much to make an unnoticeable recording device.
4) Do the instructions on the screen look familiar? Are there any unusual questions or options?
5) Cover the pad with one hand whilst typing in your PIN number.
6) If you fail to spot any cameras or dodgy blokes hanging around, you can still fool the crooks by lightly touching false numbers in between the real keypresses. This works in two ways: firstly, if any camera is focused on the keypad, it will see you pressing numbers which are not your real PIN. Secondly, crooks can polish the keys before you use the machine so that your greasy fingerprints leave marks on the keys you have pressed, which can clearly be seen when coloured powder is applied. By touching false numbers, they cannot guess your PIN number.
E.g. if your PIN number is '1,2,3,4', you can type in '9, 1, 5, 6, 2, 2, 3, 8, 4' (where the numbers in bold are where you press the key hard enough for it to register the press and the lighter numbers are where you lightly touch the keypad to leave a 'dummy fingerprint'). Remember, the more keys you press, the more you can confuse anybody or camera watching you.
Do not use cash machines unless it is absolutely necessary - get cash from a Post Office or Bank. Only get cashback from a reputable supermarket or shop where you are acquainted with the shopkeeper. Many dodgy petrol station operators are now skimming cards (my Dad recently got his skimmed in one). Do not let your card out of your sight.
BTW, I reckon the Stone Road Co-op cash machine is dodgy. I have seen it tampered with on many occasion. Do not use it! I've also heard that one of the ASDA ones have also been tampered with.
