Suppose you've decided you want to create your own divination system. There are plenty of websites that talk about it, but they're generally in very haphazard terms: just collect some symbols, and voila!
If it wasn't obvious, I'm not a big fan of that methodology, because it leads to the kinds of oracles out there that can't actually address most of the issues people have questions about. It's all well and good to consult the Angel deck for angel-related issues, but when you need to know if you should accept job offer A or job offer B, the vague responses those decks tend; whether you will read every question or not is a different issue, and the deck should be able to answer health/death/legal questions even if you don't read them.
There are two main approaches to a system, which I call Word and Story:
In the Word approach, the system uses precise components which are combined to create more details. These systems tend to be very practically oriented with down to earth and concrete descriptions. Examples would be the Lenormand or Numerology.
In the Story approach, you see each token having a complex array of meanings. How each story connects to the others is where the interpretation is made. They tend towards very psychological interpretations, and tend to go into the motivations of the people in a situation. The classic example is the Tarot, modern Astrology, and most of the modern oracles.
Both approaches have their pros and cons, but I find that people tend to lean one way or the other. Myself, I tend more towards the Word approach, but it's a spectrum and there are moments where the Story method is really helpful.
Part 1: Meanings
With either of those approaches, and with the idea that a system should be able to answer any question, I find that working through lists of meanings is a really good way to make sure you have accounted for everything (within reason).
How do you do that? Go to your favorite websites, books, blogs, podcasts, etc. and just start writing down all the meanings you can find. I made a list and add to it occasionally - it now has over 12,000 meanings. That's more than I need, but handy to have nonetheless.
You're looking for a list that has meanings from across all possibilities. Positive and negative and neutral, all the possible relationships and work situations and health and so on. You want a list that will help you spot gaps in your list of tokens. I've done you a favor, and there's a text file below, with over 11000 random meanings for you to play with. I am pretty obsessive and stubborn, but even I gave up after approximately 2000 meanings sorted into tokens.
If you'd like to build your own though, I recommend looking for meaning lists from Tarot and Lenormand websites, especially for sites that list meanings for combinations. I've added plenty of my own, just be describing the situations and people in movies and TV shows I was watching as well, just sort of absent-mindedly, casually adding as I feel inspired.
Part 2: The List
Next up, start breaking those meanings down into tokens, and start grouping them. What that means is that you take a meaning from your list, and then decide how it would be represented in your system. For example, if the meaning is "a cheating lover", then you might want a token for deceit and one for a lover or relationship.
These tokens will be the start of your system, corresponding to the components you work with. We start with the Word approach because it's easier to sort, and can then add or expand into a Story approach if needed. As an example, in Astrology, those deceit and relationship tokens might be Neptune and Venus, with other keywords in there as well, of course.
Don't worry at this point about grouping them all together. Just create as many tokens as you need to build up every meaning. I ultimately ended up with about 200 that did the job for everything I came across. After I hadn't added a new token in a long time, I figured I was basically done. For me, that was about 2000 meanings, but I bet most people aren't as stubborn as I am.
One thing to be conscious of throughout this process is that some meanings won't easily fit into a meaning-focused token. I call these literals, where you need the meaning to be literally and not symbolically present. Colors, specific places in the world, and so on - these are all candidates for literals. A good example would be "French cuisine" - you might have a token for food, resources, survival, health, or the like, but you probably shouldn't have a token for "French".
Instead, that would be a good candidate for a literal, some characteristic of the card or bone or whatever that implies French. An example might be my Oracula card meaning order and civilization - the image is the long carefully tended rows of lavender on a French farm. It represents order, but literally, it can mean the lavender plant, purple, or France. The card for Spirits is a photo of incense from an Asian temple - you can imagine the literals there. In the Lenormand, an example is using the Snake for wires and pipes.
What I do is make notes for those meanings that need to be literals. It's also useful to think of them as correspondences to include in the details of the token. At any rate, as you explore and elaborate and learn about the tokens, you may change your mind about whether they're truly literals or not. They may need to be actual meanings for the token. At the end, you will be able to look at them and figure out categories to make sure to include and assign - you've got a list of 6 colors you need to include somewhere, so it's a good bet that colors in general should be associated with every token.
Part 3: Testing
Lastly, test the bejeebus out of that list of tokens! Figure out which tokens would explain each stage of the plot in your favorite novel / TV show. Which tokens describe the characters? How about describing your car and its history? Today's headlines? Your friends' relationships?
You may find other tokens are needed. Or that some of the tokens you've already listed are confusing, and should be merged, or differentiated differently. The more testing you do, the more finely tuned your list of tokens will be.
What tokens did you come up with? Where there any that you needed that you are surprised by? How about once that confuse you or seem off a little?