We use a set of those clip together rubber mats - about $20 from K-Mart.
I have a pic at viewtopic.php?f=1&t=2952
if you want to check out what they are.
Inside the tent we nearly always end up with sand and dust. We just sweep up with a dustpan and brush before we pack up.
Mind you there are only 2 adults camping and I have been well domesticated by Jo.