We save up. My husband really doesn't like debt (which is why we rent, grrr).
But, we don't really buy lots of new expensive furniture. Our couch, coffee table, one book case and end tables are secondhand from a bid sale, our arm chairs are from my parents, our dining table's from Ikea and the bed we bought from Amart. Our fridge is on the smaller side from Good Guys (paid cash). Our other bookcases and TV unit is from Reject shop. My parents gave us our washing machine as a wedding present.
I have one of those interest free cards, but I haven't used it yet. We're planning on buying an entertainment unit so we'll probably use part savings, part interest free.