You'll need a tool to wind the piston back into the caliper.
http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_214227_langId_-1_categoryId_165727#dtab
quick question mate... where did you get your pads and disks from and how much... mine need doing asap was thinking of taking them in when its in for it service... rather than let them charge me a fortune for parts...