Baby hand and footprints in clay

Hi all, hopefully I have come to the right place! I’m not massively clued up when it comes to clay and looking for advice on how to stop the cracks with air dry clay. My baby passed away and I am able to see her once more before her funeral, so I would really like to get this perfect. Is this clay ok to use in the picture? If not, could you please recommend one (UK based)? If so, what are the steps I should take to stop the cracking? I have read to wrap in cling film or put a damp cloth over the top. Sorry if these are silly questions! I only have one shot to get these. Thank you 😊