Favorite can be either a noun (to be the most favored in a race or competition) or an adjective (to be someone's most treasured). That horse is the runaway favorite at 9-2. Twix is my favorite type...
retrace your steps means:if you've lost something and you need to find it, you would try to remember where you were and you would go from there. e.g, if i lost my phone at the park, i would go back...