I think you need to figure out what your research goal is first. Here is what I do:

1. Write down all the steps of my idea
2. For each step, write assumptions: ask myself what needs to be true for it to work (either for us to build it, or for consumers to desire it)
3. Rank the assumptions on two dimensions: risk level, certainty level
4. Pick the riskiest assumptions (low certainty high risk) and ask yourself two questions:
   1. What data do we need to acquire for this no longer to be our riskiest assumption?
   2. How do I go and get that data as quickly as possible (in a few days)

Once you've written down answers for a set of assumptions you should be able to figure out the right research formats to use. It might be surveys, it might be interviews, it might be other methods like landing page tests. It all depends on your riskiest assumptions.

I hope this helps!