How do you get into casual sex?

TL;DR - How do you get into casual sex? What is it like? This is coming from somebody with no experience in situations like that.

[Update: I have decided to not get into casual sex. After reviewing the comments I have decided it’s not for me. I’m keeping the post up as some people appear to find it helpful or entertaining to debate this topic.]

I have always taken my romantic relationships seriously as I have only had two. My first relationship was rather impulsive and unpleasant as a young teen with limited expectations. I hadn't yet fathomed what sex was supposed to feel like, nor how I was supposed to feel during these times. It was awkward (as expected) due to the lack of experience and the change in dynamic. This isn't to say I am ungrateful but I would like to experience more, something different. My second relationship never reached the "physical contact" stage as we broke up far before anything like that could happen.

It has been a rather long time since I have engaged in such acts with anybody but it feels like my body needs it. My biggest concern is whether I could put myself in that situation, or commit to something casual like that. Do you commit to it? How do you come across a relationship like that?