Step Three: the ropes
Nudge. Start from what is fixed: one bell has its place given outright, and two pairs have to sit together in a stated order.
Harder
Fifth last. Two then four, somewhere before the tenor; the tenor, then the treble at once. That leaves the third one place to go that is after the second and not beside the fifth.
The step, in words
Six buttons, lightest to heaviest: Treble, Two, Three, Four, Five, Tenor. Tap them in the order you want them rung; the order so far is read out after each tap. Ring commits the six; Let go clears them. The slip's six rules are the whole puzzle and are printed above the ropes.
The answer
Two, Four, Three, Tenor, Treble, Five: 2 4 3 6 1 5.
The fifth is sixth. Two-then-four and tenor-then-treble are pairs, with two-four before the tenor. The third comes after the second and cannot stand in fifth place beside the fifth, so it goes between the pairs: two, four, three, tenor, treble, fifth. The bells go out over the brooks in that order and the reeds part.