Hi.
You need to put the card in the correct slot in your Sky box. You need to go into the Services - System Details menu on your box and put all the information (including the viewing card number) in an email to your cousin and then get him/her to call Sky to activate it. If the viewing card number is not shown then you have not inserted it correctly. He/she will need to pretend they are using the system and have followed the customer service persons instructions to get to the System Details screen. Alternatively you could call Sky yourself but
make sure you withhold your number or they will know you are overseas. If you cant dial their 0844 numbers from there then it is usually possible to find a real number for their customer services on this forum (-http://www.saynoto0870.com/cgi-bin/forum/YaBB.cgi?num=1060112694/1031#1031).
You will get ITV1 and ITV1 HD in your location. You may need to tune them in using "Other Channels". They are at 11973 V 27500 2/3. If you have the wrong Channel 5 region (i.e. your parents address is in southern England excluding London, Wales or Northern Ireland) then the receivable versions can be found at 12422 H 27500 2/3 to add via "Other Channels". You will get Channel 5 HD on the EPG. You will get Channel 4 HD on EPG at present but it may move in April. You can get most BBC sports events by going to channel 503, pressing the red button and then choosing page 3001 (you don't need the viewing card for this). You could also use one of your FTA boxes to see all of the BBCi transmissions (including the sport) they are at 12441 V 27500 2/3 but you can't add them to a Sky box. Obviously if you don't have a suitable box you will not receive the HD channels I have mentioned.
BTW - if you decide to subscribe to Sky they can add a subscription to that card. When I did this they gave me 6 months half price (although that was a few years ago).
According to these maps -http://www.flysat.com/astra28-beam.php you might pull in the 2A North beam lobe if you have a 1.2m dish. Channel lists for the various beams can be found here -http://www.flysat.com/28east.php
Good luck. I don't think you can go too far wrong