Pit Firing

Pit Firing is the first way to fire clay into bricks, clay molds, jugs, pots, and more. You will have to do a lot of pit firing in the early game.

Collect some straw, logs, and clay.
Place a single straw into a hole in the ground that is surrounded with dirt on all 4 sides.
Right click the unfired clay items onto the straw to place them in the pit. There will be room for 4 items.
Once all your items are placed, right click several more times with straw to fill up the hole until no more can be placed.
Place 4 logs into the pit by right clicking into the straw again. This should fill it up to the top.
Using two sticks, light the top on fire, and wait for the process to complete.
After it is finishedd, the items will be in a pile of ashes that can be dug up with a shovel.

Pit Firing will take about 1 minecraft day, depending on how many items are being fired. If you need items as fast as possible, fire fewer items at a time
Designate an area for firing and dig a grid of holes to easily run and organize multiple pit kilns at once

To create your first tools and begin to cast metal parts, you will need to use a pit kiln to melt your metals down.

You will need to follow the same process of setting up regular Pit Firing.
Get a Fired Clay Vessel. Clay vessels can be right clicked on while holding items in the inventory to add items into them (like a bundle).
Once you’ve added enough metal items and are ready to cook it, place it in the Pit Kiln like firing any other item.
After firing completes, the vessel will be filled with molten metal, comprised of whatever metal items were added to to vessel before firing.
If you only added one type of metal, it will have been melted. If not, and the ratios of metals matches an alloy, that alloy will be created.

With a vessel full of molten metal, right clicking over a clay mold will remove one ingot’s worth of metal from the vessel and place it in the mold.
Molds take different amounts of metal to fill, based on what the vanilla counterpart would require.
Once enough metal is in the mold, you can craft the filled mold into the corresponding tool part.
If you accidentally fill the wrong mold or can’t fill it all the way, a partially filled mold can be crafted into metal chunks equivalent to the amount of metal contained, and the chunks can be re-melted in a vessel again.