Worldbuilding is an artistic skill like any other, and it takes practice to flex those creative muscles to develop great worlds.
Or, to put it far more negatively: your first world sucks. Just like the first story you ever wrote sucked or the first drawing you ever drew sucked. What a bummer.
But let that knowledge give you creative freedom. Don't worry if your first world is any good, and instead use it as a way to practice, as a way to express yourself. Throw all the clichés you want into it, make it incoherent, unintelligible, embarrassing to expose; it's perfectly alright. By practicing with your first world (or first few worlds), you learn what you're good at, what you need to pay attention to, what works and what doesn't, and what's awesome and what isn't.
Make your first world be full of elves and dwarves, or make your first world be based on a nonsensical dream, or make your first world mind-numbingly silly. Use your first world to explore. You're not exploring a world, but rather you're exploring your mind. You're learning about yourself. Make your first world deeply personal, as well as completely childish and terribly immature.
Your first world should be like writing your first poem: absolutely awful when you look back at it in two years.
The first world I can recall making, at age eight or so, was a map of a dinosaur theme park a la Jurassic Park. It was bad. Then I made another one just like it. It was also bad.
I made many nonsensical worlds, worlds based on dreams I had or just letting my imagination flow, go wild, and see what it could come up with. They were bad. All of them.
It's not that I wanted to make nonsensical worlds, it's just that that's all I was capable of. I didn't know how to create a coherent world.
But as I grew as a worldbuilder (and grew as a person), I started to pull from outside sources, which stabilized my worlds a bit, made them more coherent and cohesive, but drowning in cliché. I made a world with elves and dwarves, but modernized it (we call that genre Urban Fantasy). It sucked, but it was followable. I made a world with gods and demigods and centaurs in a post-apocalyptic medieval setting. It sucked less.
How many worlds have I gone through? I've never counted, but dozens at least. Most of them sucked. But all of them were practice for the next one, which sucked less.
That urban fantasy world I made was based off real life, with people I knew as the characters in it. I put myself into it, as well, and wrote those characters as how I saw those real people. That world wasn't an escape so much as it was an expression of who I was.
For a very long time, my worlds' protagonists were unable to find happiness, searching in vain for it but not knowing where to look or where to begin. Those protagonists were me, as I was creating new worlds to escape to, to find some kind of fun and happiness when the real world presented boredom.
In college, I got a long-distance girlfriend. I'm American, she's Australian. We fell in love online, but did not meet in real life until over a year after we considered ourselves a couple. That was a year for heartache and longing.
While in that relationship, I came up with at least two worlds where the central theme was lovers unable to touch. One was a short story about penpals who lived on different planets, who fell in love over the years. It was touching and it was tragic. Perhaps I'll post it to Hubski sometime.
Another world based on that relationship was a design for an RPG/Adventure game, where two characters lived in different mirror-image dimensions, and could communicate through dreams. They fall in love, and quest to find a way to go between dimensions so they could meet face-to-face. Even more touching, even more tragic.
These worlds were expressions of myself, and my feelings, just like previous worlds, but I had had enough practice (and a new inspiration), that these worlds started to get good. The penpal story was read by a creative writing class, and at least one girl said she cried over it.
That's when I knew these worlds weren't just for me anymore. They were good enough to share. They weren't just nonsensical or cliché-ridden affairs that appealed only to my bored mind or teenage angst. They were places that people could get lost in; people could feel in.
It took me fifteen years of worldbuilding to reach that point.
You have an advantage over me. You can reach that point in shorter time. Much shorter. You can breeze through my struggle to create solid worlds, to throw away cliché, to make something original and touching.
You must still practice, of course, but you don't have to practice alone.
I told you your first world sucks, but that's no reason to keep it hidden. When I was growing up, I never got to see behind the scenes. Movies were on VHS and there were no deleted scenes, bloopers, or making-of featurettes. Novelists didn't show you first drafts of their work, and you never saw an artists' scribbly sketches.
Now you have all that, and it's becoming the norm to watch the process of creation, to read the sloppy first drafts and play the buggy games in alpha and hear the song demos.
Show off your works in progress, show off your first world. Hear from others what's confusing and confounding, so you can create a more cohesive, coherent world. Ask pointed questions about what can be improved, get taught by example where those clichés are to avoid. I said at the beginning of this post:
...But expose it! Post your first world, whether you're proud of it or ashamed of it, it doesn't matter. Let people give you constructive criticism, and use that delete key like it's stuck. Erase, fix, edit, add, erase again. Maybe you'll get sick of that world and you'll throw it away and start a new one; that's what I often do.
But maybe that world is too precious, maybe it's worth saving, fixing, getting right, evolving into something better than how it began. Maybe the wrapping is ugly, but the candy core is sweet, and you can remake your world over and over from the ground up, until you get it right. Until you get it good.
As you worldbuild, as you see others' worlds, as you critique and get critiqued, you'll become better; perhaps you'll see the errors in another's world first, and realize the same errors are in your own. Maybe you know something is wrong, but you need another pair of eyes (or twelve) to take a look and point it out.
Practice, post, critique, and you'll soon be making amazing, touching, beautiful, cathartic, original worlds. (And it won't take you no fifteen years neither.)