Rings as anchors
When my husband and I first opened up this relationship (I've been poly most of my life, he's new) I found that I was thinking of D.H. when I was with A, and A when I was with D.H.
I'm a kinesthetic person, so I picked one of my rings that seemed to fit A and wore that on my right index finger. I have a simple gold band on my left ring finger for a wedding band. When I was with either, especially in moments when confusion would be very bad form (ahem) I would touch the appropriate ring and fidget with it to anchor me to that relationship.
I now have another man, B (and it amuses me to no end that their initials are lining up like this). A has always been more of a friend with benefits. We talk, we play, we shag the daylights out of each other, but he is very comfortable with the role of "stunt cock." B and I have a much more emotional relationship. I can see myself having kids with B in the future. A I would just like to be around so he can tell them stories and pass on wise words (She's an adult, she doesn't need rescuing).
So, D.H. gets a wedding band, A has a ring of frogs on the right index, and B has a claddagh on my right ring/middle finger with the heart pointing in. the fingers vary because if it's chillly out it slides right off my hand. I've also lost a bit of weight and have to wear another ring distal from my wedding band because I've flung it across a room in conversation. Sometimes I also wear a plain silver band on my right thumb that I set an intention or motto to, kind of like a string around the finger. I want to get it engraved, but I keep changing my mind.
And then there are days when I take them all off because I want to be my own for a little while.