In the past few weeks I have really been making an effort to mention the colour of everything. Somedays I thought she was starting to recognize them but then others it would seem like it wasn't sinking in yet. Yesterday she pulled out her Mega Blok cars. I disassembled them. Whenever she plays with them I try to point out that you can match them up by colour, and yesterday she matched them all up and put them together on her own 3 times in a row. Just a month ago she couldn't even fit them together on her own.
I was thinking I would make some coloured parking spots for her to drive them into so she can do some more matching.