Velez had never puppeteered before joining the Jim Henson Company. In Henson puppeteer workshops starting in the 1980's he was taught and trained in the art of puppetry by Richard Hunt, Jane Henson, Jim Henson, Frank Oz, Kermit Love and Caroll Spinney.
In-house company training and Velez's ability to mimic voices has led him to audition for opportunities to backup the established Muppet characters.
- Sesame Street: Osvaldo, el Gruñón
- Muppet Meeting Films
- The Muppets Take Manhattan
- A is for Asthma: Dani
- Elmo's Christmas Countdown
- Pappyland: Turtle Lou
- Velez, Ron Mueck and Shari Weiser were placed in an acting class by Jim Henson, and taught by Cheryl 'Gates' McFadden
- Velez made an on-screen appearance as a library patron in Episode 2924 of Sesame Street.