-Getting started-
First of all, make sure the mod is properly enabled and loaded. Then, make a new world and character.
The start is not far off from vanilla: Dig, build, explore, fight.
During your exploration, you may encounter a few new things:
Chozite Ore, Chozo Statues, and Missile Expansions.
Note: Chozite Ore requires 50% pickaxe power to mine, though Chozo Statues do not have this requirement. Mining a statue will net you additional Chozite ore. (Personal statues can be made out of regular stone, and mining them does not give you ore.)
Every statue you encounter will have an item resting on its hands. Almost every item you find will be unusable, however, but save them for later. Same goes for Missile Expansions.
Continue playing until you're powerful enough to defeat the Eye of Cthulhu. Chozite Armor can be made out of Chozite Ore.
Not exactly a Power Suit...
yet!
You may have noticed an odd icon on your map.
Heading over to it will take you through the desert to find...
The Chozo Ruins!
The doors can be opened with Right Click or by firing a projectile into them - though I suggest saving your arrows if that's what you're using. You're gonna need them.
If you venture through the ruins thoroughly, you'll find:
-A magic carpet
-Morph Ball
-Missile Expansion
-Sandstorm in a Bottle
-Morph Ball Bombs
-Power Grip
If you've found any Morph Ball addons during your previous explorations, you can now use them with the Morph Ball.
You'll know you're reaching the end once you see a Save Station (it's actually just a fancy bed).
Set your spawn point here, if you want. Or don't. Either way, you're about to fight a boss (in case it wasn't obvious).
Suspicious Chozo Statue is suspicious. This thing is larger than any other statue, and boy that Energy Tank seems tempting... But any veteran Metroid fan may know what'll happen if you approach it.
I hope you've brought plenty of arrows for your bow, or have plenty of magic for your magic weapon... or just plan on swinging a sword into it. Either way, it's time to fight the
Torizo.
Defeating it will yield some Chozite Ore, and also Energy Shards - a much needed resource. With Energy Shards and Chozite Bars, you can craft the Power Beam! Pew pew!
But also remember how the Torizo was holding an Energy Tank? With these Energy Shards, you can craft Energy Tanks. However, to do so, you will also need Shadow Scales (if on a Corruption world) or Tissue Samples (if on a Crimson world). Which means you need to fight a vanilla boss: Either Eater of Worlds or Brain of Cthulhu.
With Energy Shards and Shadow Scales/Tissue Samples in hand, crafting Energy Tanks is now doable. You may now use Energy Tanks to convert your Chozite Armor into...
The Power Suit!
-Insert Samus intro fanfare here-
The guide ends here. I will write more in time, but for now, explore and find out things on your own for awhile. I hope the design of this mod is intuitive enough so that you won't need a guide too much to figure out what to do next. If it isn't, feel free to submit suggestions on how to improve it. Also if you're stuck on what to do next, simply ask and I'll answer to the best of my ability.
You can also use the mod Boss Checklist to help you figure out what to do next - this mod is fully compatible with it!