In the first recording track, I've selected everything in front of where I started recording in that track.

Then I do Generate -> Silence to retain the space of the intro.

To join the two verses, I do Generate -> Silence again from the end of the first verse's track, to where I started recording on the second.

Then I copy the lower track to the upper one.

And delete the lower track. I repeat these last two steps for however many verses I had.

To edit out mistakes, I delete the end of the track, keeping in mind where I started over in the next track (in other words, I delete to a place where the join won't be noticeable).

And then, I set my cursor on the next track, at the point where I just deleted from the previous one.

I select through to the end of the track and cut and paste it into the top one.

Then I delete the lower track, and repeat for however many mistakes I ended up making. I should note, that in this example, I have a separation between connecting verses and editing out mistakes, but in reality, I just move from the beginning of the recording through to the end, so I might do two mistake corrections, then a verse join, then another mistake correction, then a couple more verse joins, and so forth.

Finally, I delete the midi track.