At naptime, we created a routine for going for his nap, but did sort of a mini bedtime routine because we didn't want him to sleep for 8 hours at naptime so we didn't pull out all the stops for the nap routine. For bedtime, we had dim lighting 2 hours before bed and quiet games only, snack an hour before bed, bathtime, massage, songs, books, cuddles and sleep. So for naptime, we did a smaller version of this: about 15 minutes before nap we make sure we're slowing down activity so that he wasn't running, or playing horsey rides with daddy, or screaming and being overstimulated or anything and then SUDDENLY have to be thrown in the crib - it's kind of waaaaay too much of a contrast to go from hyperactivity to being told it's time to be unconscious

! So after 15 minutes of calming down, we'd go to his room, read nap books (Time for naps - Jane Yolen for example), sing a song, cuddle then sleep... so no massage, no bath, no snack (because presumably lunch was a half hour to an hour before nap anyway)... and we don't worry that a bit more light is coming through during the day than you'd see at night because it's not supposed to seem the same.
Hope this helps!