1 Proceeding to the midst, he still did stand, 2 As if in mind he somewhat had to say,
somewhat > something
3 And to the vulgar beckoning with his hand,
vulgar > common people (typically, the groundlings in the pit of the theatre)
4 In sign of silence, as to hear a play, 5 By lively actions he gan bewray
gan bewray > did reveal
6 Some argument of matter passioned;
argument > subject-matter [of the show about to be performed] matter passioned > [the] matter expressed [in the show]
7 Which done, he back retired soft away, 8 And, passing by, his name discovered:
discovered > revealed