One of my favorite pastimes is to make things go *boom*, I often use homemade black powder to do so and here is a fun way to spend your weekends. The ingredients listed can be purchased online or at any local hardware store with a "outdoor / gardening" section. However the production from scratch is simple and can be done over the course of a year depending on how much time you invest in the manufacture. I do however recommend using store bought components.
While not needing all listed ingredients, you can get away with using just Saltpeter and Charcoal, while Sugar, Alcohol, and Sulfur are used as an accelerant in the core mixture. To test mixtures its best to scale down the compound into manageable amounts, mixing together to cover the bottom of a pie pan, or to be mixed and added into something the size of a tea bag will let you experiment with the mixture amounts. The recipe will differ on the purity of the ingredients, the weather conditions such as humidity, and the wind.
To begin to will use to base total measurement of 100. So for example is something calls for (75 parts: Charcoal) then the remainder should be some sum of (25).
Core Mixture: (75 parts Saltpeter) + (25 Parts Charcoal) - This is your core mixture, the most basic form of black powder that will ignite and combust evenly. This alone can get you going to a more even or more accelerated reaction. I recommend this for those looking to experiment.
Sugar Mix: (70 parts Saltpeter) + (10 parts Sugar) + (20 parts Charcoal) - Using sugar as an accelerant will allow for a more even reaction with more combustion. Be careful as with the wind catches this while testing, if the particulates are still close enough in air, it will continue to light.
Sulfur Mix: (70 parts Saltpeter) + (20 parts Charcoal) + (10 parts Sulfur) - This reaction is going to be fast and loud. Sulfur is highly reactive and this mix will be much more powerful than the Core or Sugar mixture. While Sulfur is common in nature (Fool's Gold or Pyrite) it can be hard to find in a survival scenario since its most common near caves, volcanoes, or hot-springs.
In order to make the mixtures in an even and controlled environment, there is a quick process to follow to ensure the best result.
Charcoal: Make your charcoal. Place the wood chips in a large pot with a lid or a 55 gallon barrel with a lid, just make sure there is a little open area. a drilled hole in the lid or crack will do, so some steam can escape. Build a fire under your container. When steam begins to exit the container, light the wood inside and re-close the lid. Let the fires burn out and wait for everything to cool. What is left inside your container is your charcoal. Good wood for Charcoal is the same as Lye.
https://www.skylighter.com/blogs/how-to-make-fireworks/making-high-powered-black-powder
https://www.survival-manual.com/gunpowder.php