The short answer:
You got to learn that.
The long answer:
Sound design is a wide area and you need a lot of experience, good ears, knowledge, ideas, visions, and so on. You cannot just learn sound design in common. Every sound designer works in a specific area. Nobody can tell you how to design sound, only how to design a particular sound. So, if you can describe a sound in detail or - much better - post a sound example, here are several people who can tell you about methods to create such a sound.
Btw, you said metallic and water, for that you already had a good tool under your fingers, Sculpture. This is a very powerful synth and works with physical modeling. It is very complex like any other physical modeling software and you need some time to get familiar with it. Sculpture simulates vibrating cylindrical objects. You can modify the dimensions of the object (I think), you can choose and morph the materials and the virtual object can be plucked, bowed or blown.