Freelancing takes some degree of ambition and if you're just starting it can be time consuming.

What I'm hearing though is you want the benefits of freelancing without having to do the work of a freelancer? That's a huge fallacy. Freelancing requires some degrees of ambition and most importantly work.

Unless you've built a reputation for providing these services its going to be difficult obtaining customers.

What should you do? At the very least

  - build your profile and build your brand
  - "become" an "expert" in your field by blogging, tweeting, etc to drive engagement
  - get connected to other "experts" and start conversations
  - build a simple landing page (site) for each area you want to provide services for. A/B test the landing page using Google Ad Words, etc
  - sign up as an organization on freelancing sites and start doing jobs which can be done asynchronously
  - become a maintainer or contributor to security auditing software

Alternatively you could buy an existing business and improve it.

Again, all this requires ambition and work.

If you don't have time or interest in finding the time it's probably not for you.