What ever you have been doing doesn't look too bad! That is a real jewel.
In general keep it clean, dry, and lightly oiled, except for the grip panels.
Everybody has their favorite oils, I put Breakfree clp on the guns I use often. There is some stuff called rig grease that can be applied to the metal for longer term storage , or some stuff called Renaissance wax if you are not going to fire it. Gun oil isn't good for wood, so leave the grips alone, also be careful if you remove the left grip as they are notorious for breaking by the safety. The so called "million dollar chip" can be avoided if the grip panel is slid down, do not lift it up. The leather in the holster can draw moisture, and has some salts in it from the tanning process so some don't store the guns in the holster. There is a liner that can go between the gun and holster, but I have no experience with those.
This is a good article on conservation;
http://gpigun.com/Preserving.pdf