I use this electric steamer (bought on sale for $20). You can also use a metal steamer basket ($8), which are cheap and don't take up any extra kitchen real estate since you can store it in your pot. Or you can just line a really big pot with a tiny bit of water, bring it to a boil. Add the sausages (fold side up so no water gets in), but then keep an eye out the entire time because you'll need to add more water periodically because you'll burn the sausages (and your pot!) if the water runs out.