To stay sharp, keep your eyes peeled, or be on your toes in a given situation (the term maricos in the example is a vulgar slur for gay men that, in Venezuela, is used casually between friends like dudes).
Dudes, we have to stay juega vivo in case the teacher shows up.
A person who follows someone else around all day, sticking to them like glue. (The term literally means glue-sniffer, referring to street kids who inhale solvents; it is used figuratively for someone who is overly clingy.)
Are you ever going to stop following Miguel? You are like a huele pega. / How much longer are you going to be a huele pega, man?
Someone who hovers around or follows a person, pestering them or waiting for an opening (the term refers to a vulture, implying the person is circling someone like a scavenger).
You look like a zamuro chasing after that girl. Stop following people around like a zamuro.