BJD making advice?

Welcome to the world of doll making!
I have few suggestions:

Test your materials: I always nag about this one, but I've seen so many projects stalled, delayed and money and materials wasted just because en enthusiastic beginner decided that testing their materials was too much work or that they probably didn't need to do it beacuse - insert exuse here-...
Just do it. Do it early, do t aqgain when you change out any of the parts tested. Test your sculping material with your primer, test a primed piece with the silicone, test the mold releas, test the resin. Test it in the enviorment you will be working, check temperature and humidity when testing. Document you results.
It doesn't have to be tedious or take very much time or materials and it can literally save your entire project down the line.

Cores:
1. Keep casting in mind when making the cores. The shape of the core should be as close to the desiered shape of the inside of the part as possible to cut down on work you have to do to finish the part later. If the core shape is such that it can be easily slid out of the part, that's a good sign the mold will be easy to slide out as well.
2. Core material has to be cosen with the sculpting materials in mind, perhaps state the intedended materials right from the start, for easier reference in the future.

Sculpting:
There are many ways of going about it, the comment about "clear out a place for the joint" that assumes a certain process for creating the joints that are not previously established in the document and reads as out of place and confusing. There are other methods as well, such as starting with the ball of the joint and sculpting the socket to match, or using a placeholder to cut down on work time and waste.

Prepair the parts for casting: I miss the step of preparing the parts for casting. This step can take quite a lot of work, often as much as the sculpting itself and I would recommend adding it as it's own step, rather than just adding it like a footnote to the sculpting, as it is usually a lot more about endless priming, sanding and adjusting than it is about actually sculpting.
Also, if you have added someting like s-hooks and bars for test stringing, these have to be removed before casting.

Plan the molds: This may be covered by the video you link to, I don't have time to watch it, but I would argue that this step is probably as -if not more- important than making a blueprint of the doll, as this step needs to be thouroughly thought trough and will be one of the deciding factors of how your casting will go. Especcially if you do it for the first time you need to really think about how each piece needs to be cast. An experienced caster may be able to just look at a piece an know how to align it, where to place the vents etc, but for a first try, this takes planning.

Casting: again I don't have time to watch the video, so this may be covered.
1. you are being very general here. You leave out a lot about equipment, types of resin etc, but mention using acrylic paint to tint it, something that will not work at all with polyurethane as is a water based paint and thus would add moisture to a product that really hates water. It makes no sense. Proper pigments are important and so is, again, testing them beforehand.

Demolding and cleaning up the parts: This is another step that I think is missing. You may want to include it in the casting step and that would be fair, but as it is it sounds like the pieces are magically finished and ready to be assembled and painted when the casting is done and that's missleading.

I'm not ging to comment on the face up etc, since that is not something i'm very skilled at and has nothing to do with the sculpting and casting process.

Over all, I think that while collecting your knowlege in one place like this can be very useful for presonal use, if you inted to share it with other beginner as you state in the introduction, you should probably get mose of your own experience and flesh it out a bit more as many things seem to be just left unsaid. If you intend to teach, make sure what you teach ar based on your own knowlege and not just random sources repeated out of context. Many of these steps are arts in their own right and entire books can be written on topics such as these, so wile simplifying it for you own benefis may be useful, it's easy to accidentally make it sound like a much smaller projects than it really is and that may misinform and hust more than it helps.

So, to practise what I preach: I have many years experience with sculpting in polymer caly, limited experience with air dry cay and limited experience with epoxy clay.
I have some experience with moldmaking, including moldmaking in silicone, without the use of a vacuum chamber, for casting doll parts out of polyurethane resin.
I have a fair bit of experience with casting said resin in said molds without the use of a pressure pot.
I am (finally, it has taken a lot of trial and error) at a skill level where I start to ger consistently good casts enough of the time for it to pay of.
I you have any questions or want more information on any of those topics, feel free to ask.

 

I'm sorry if I missundestood you. I tried to add several important things that I thought you missed, but if I missunderstood you I apologize. I was just trying to help.

 

It depends on what you want to add? I thought @Lillith had some good points. Especially that acrylic paint isn't used for colouring or dyeing (rit dye is a popular one for dyeing already cast and completed resin dolls) But the other side is there are a lot of options for materials that are missing (ie: la doll clays are popular, plus there are various epoxies and mixtures of them preferred by different people. And there are all kinds of sealants and primers. Plus there's 3D printing, which is a whole world of even more options!)

But if it's just a document for your personal use, then just start, and ask for specifics when you run into them. There are many different routes to making a doll, so there is sadly no definitive "you need x, y, and z" answer.

Good luck!