I am making some Valentine cookies for my little sister's class. I need them a few days early so I'm getting started tonight. I'm doing the ones off the wilton site that look like a heart postcard with cutout fondant on top. When do I write on the fondant? I'm in the middle of rolling them out now. Do I write on them as soon as I finish cutting them out or do I let them sit for a while? Do I keep them airtight or do I let them sit out and harden? Is it hard to write on them without making finger marks and stuff? Sorry...I'm never worked with fondant at all before so I'm not sure how to use it.
Thanks soooo much for your help!

you gotta let them sit for a little while!!! the MMF will stiffen up some and you need it to do that......just let them sit uncovered for an hour or two and you should be fine to right on them.........I have even left the fondant cut outs out all night and they get really stiff and then when the cookies come out of the oven.....I stick the fondant cut out on top and it will melt and then stiffen up again once they're completely cooled and stiffened up then you can write on them with no problem.