We took a cabin sized wheelie suitcase and it was fine, if you also take a handbag you must be able to put it inside or it will also count as hand luggage. The main thing is dont take any drinks or liquids, just buy them after passport control.
I think any liquids purchased after passport control must have the receipts and be sealed up until you arrive at your destination, I might be wrong so I'll check the airport for more information.Hope this link works fingers crossed. http://www.manchesterairport.co.uk/web.nsf/content/PRSecurityUpdate