I always use soap slivers - whatever brand is on hand. A few co-workers bring theirs to me at work - by their smell they're probably dove or ivory. Depending on my quilting template - like, if I have a plastic one, I make a pouncer with baby powder and that's worked too - it can be hard to get the soap into the template lines without making a mess of the plastic template
I've also made a pouncer out of cinnamon for my lighter fabrics. My quilting might not always look the best, but it always smells good
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