First, don't buy your pig your pig from a petstore. Find another pig on craigslist or petfinder or at a shelter. Next you will need a large space where neither pig has been before. Have a pile of hay and veggies and put one pig at each end of the area/pen. Normal things are mounting, rumble strutting, teeth chattering (to a certain extent) and butt sniffing. Don't take the pigs out unless there is bloodshed or fighting. Also quarentine is a must for 3 weeks until you make sure your new pig isn't sick. You can skip quarentine but there is a risk of letting your pig get sick. Also let your new pig settle in before you introduce it to Sugar.