Bismihi ta'ala

The rulings related to jewellery and items that have verses of the Quran, names of Almighty God, and also names of Ma'sumeen (a.s.) is that the script must not be touched unless one has wudhu', and that it is not contaminated with any najasah. 

If you have a ring, or a pendant, or something that has such script on it, and you know you cannot avoid touching it, or it touching your skin and you might not be on wudhu', then one thing you can do is cover it with a layer of colourless see-through nailpolish. 

With the layer over the script, you will not have a problem if you are not in wudhu', and you touch it, or it touches your skin. 

As for when you go to the toilet, you do not necessarily need to remove the jewellery, as long as you keep it away from najasah. If you think it might be contaminated with any najasah, then it is wajib to remove it. 

And Allah knows best.