Click Here for ring gap orientation when installing the pistons back into the cylinders.
If your piston engine kit came with instructions, always follow those (if you intend on retaining a warranty).

Removal:
Some just peel the top 2 rings off by hand the same as removing the oil rings.
Older rings were notorious for breaking when one end was spread too far vertically.
This still can happen on modern rings but they can be carefully wound on / off by hand.

A piston ring spreader is used below.
The ring spreader hooks both ends of the ring and spreads it apart making the inside diameter wider than the piston.
Then you simply center the widened ring around the piston and lift it up and off.

Caution: only spread the ring just enough to remove / install the ring. ¹⁾

The top 2 compression rings come off first and exactly the same way.

The oil rings are usually removed by hand.
Locate the split on the top oil ring, hold pressure against the opposite end so it doesn't move.
Carefully lift out and up at the same time on one end and try to raise that end at least to the top of the piston before letting go.
(so you don't scratch the side of the piston)
Then push out and around at the same time until the ring is out of the groove. ²⁾

Locate the split on the bottom oil ring. ³⁾

Remove the bottom oil ring in the same fashion as the top oil ring.
The expander ring comes off the same way. ⁴⁾

Installation:
Installation is in reverse starting with the expander ring.
The clearance is tighter if you install the top / bottom oil rings first and it just wastes time having to take them back off to get the expander ring on.