Translation:You wake up Marcus before the first hour.
Interesting, I love his voice. And I also love Tamara Levitt's voice (the woman who does the "Daily Calm" mindfulness meditation on the app Calm. It has been said that she also sounds patronizing. But I do agree with you in that he makes every sentence he says sound like it's part of a Roman speech. Imitating his intonation (and I mean mimicking it, out loud) can help us internalize both the language and the culture it represents.
Excita! or, if Marcus is a heavy sleeper and/or wakes like a psittacus ebrius, then: excitate!
Imperative is particularly easy with the 1st conj. verbs (-are), because you take the infinitive (excitare) - which you generally need to know in order to know how the verb conjugates [the 'pattern' it follows] - and: swap the infinitive's R for the imperative's T.
Then if you need a singular imperative, just drop the -te ending; or alternatively just drop the infinitive -re ending, to get the singular imperative directly.