You get an idea, ok good, now what?
I personally search for keywords and see what others have made. Ask right and left people, post on reddit and communities like this one.
But still, there may be like max 10 people that like the idea, do you consider that validation?
Do you then make and MVP and show that for more validation or do you search for more people to like the idea before even starting the MVP?
What's your take on this?
One strategy used by lots of startups is to create a landing page. So just create a simple landing page that takes email address and then send traffic to that landing page.
Depending on how much people are interested, you can know the level of interest.
Here is a story from Y-combinator backed Doordash who started operating just by a simple landing page.
Talking to users and getting an idea of whether they like the product
If they like it, make something small and try to get them to USE It (this is harder)