Good game audio is mostly craft, not budget. A small game with thoughtful sound feels alive, and a big game with lazy sound feels cheap. The good news is that the techniques that matter most are free to learn and the starter tools are free to use. Here is where we tell people to begin.
//Layering is the whole secret
Almost no satisfying game sound is a single recording. A good impact is usually three or four sounds stacked: a sharp transient for the click, a body for the weight, and a tail for the space. A coin pickup might be a real coin sound, a soft bell for sweetness, and a tiny whoosh. You build the sound out of parts, each one covering a different part of the frequency range. Once you start hearing sounds as stacks instead of single clips, your audio jumps in quality immediately.
//Variation kills fatigue
The fastest way to make a game feel cheap is to play the exact same sound every time. Footsteps are the classic offender. Real ears notice repetition instantly and start to grate. The fix is variation: record or make a few versions of every repeated sound and pick one at random each time, with a little pitch and volume randomness on top. Even three variations on a footstep, with slight random pitch, will sound natural where one perfect clip sounds robotic.
//Mix for the moment, not for the speaker
Game audio is not a static mix like a song. The mix changes with what is happening. When a fight starts, the combat sounds need to cut through and the ambient bed should pull back. When the player is reading a quiet menu, everything else should drop. We think about a small budget of attention and decide what gets it at each moment. If everything is loud all the time, nothing reads, and the player ends up turning the sound off.
//Free tools that will take you far
You do not need an expensive library to start.
//Record real things
Some of the best game sounds come from household objects. Crumpling paper, snapping celery, tapping a mug, scraping a box. Recording your own foley gives your game a texture no stock library can, because nobody else has those exact sounds. It is also the most fun part of the job. Hit things, record it, layer it.
Sound design for a first game comes down to a few habits: build sounds in layers, vary anything that repeats, mix for the moment, and record your own where you can. None of that costs money. All of it costs attention, and attention is what makes a small game feel like someone cared.