This quick walkthrough shows how to organize a busy Ableton Live session, in this case 16 tracks, by grouping related instruments together. Select adjacent tracks by clicking one and shift-clicking the rest, then right-click and choose Group Tracks, or just hit Cmd+G on Mac or Ctrl+G on Windows.
Once grouped, click the arrow icon to expand or collapse the group, keeping your session view clean when you don't need to see every track. The group also gets its own mixer strip, so you can control overall level and processing for the whole bundle while each track inside still keeps its individual mixer settings.