It depends what material your vibe is made out of. Some are porous, and so cannot be disinfected at all, even with the vibe cleaner you can buy in stores. Others can be boiled, and still more can just be cleaned with hot water and soap. However, sometimes when it doesn’t say that on the care instructions, it is because there are mechanical components to your toy that may be ruined when wet.
I would recommend looking into the material your toy and the way it is made and then do a google search to see if it is compatible with water. If it is not water proof, do not submerge the mechanical/electrical parts in water. Make sure you remove the batteries and clean the parts of your toy that you can clean.If using soap, make sure it is mild.
If you look into your toy material and it is not the kind of toy that can be properly cleaned and sterilized, I would reccomend simply putting a condom on the toy each time you use it.