crib to toddle bed

bee • ♥️💙
My daughter is almost 2 and I'm hoping to get her to sleep in a toddler bed by then. I'll be making her bed frame and just using her crib mattress until I get a new one. I first want her to get use to the idea of no bars and etc. Do you think it's a bad idea to start her off with the mattress on the floor then put it on the frame?