If I have to point out one strategy that will validate your SaaS startup in the most efficient way, it would be 'The Credit Card Swipe Strategy'.
Everyone can say that your SaaS idea is great, but until someone enters their credit card info you will never really know.
Here’s how you can conduct it:
Design a landing page that describes your SaaS product and its features.
Use product screenshots or Figma UI files.
Make sure it is clear and concise and highlights the value proposition for potential customers.
Include a button with a call to action to sign up to your platform.
Inside the sign up process, include a step that requires the user to leave his credit card information.
It is of upmost importance to clearly indicate that the user will not be charged yet.
It is also very important to give your potential customers something in return.