awake, understand
寤 centers on waking from sleep and, by extension, coming to understand something clearly, as if waking up to a realization.
寤 combines 宀 (roof) and 爿 (bed) with 吾, which likely provides the sound. The structure suggests waking up in a house, but the exact historical development is uncertain.
Under a roof 宀, on a bed 爿, the sound 吾 (go) calls you to wake up and understand the day.
For ゴ, imagine waking up and saying 'Go!' to start the day: Go -> ゴ, and you are awake and ready to understand.