https://www.amazon.com/Slicing-Pie-Funding-Company-without/d...
https://slicingpie.com/
The idea is to dynamically adjust equity based on how much everyone is contributing.
Some people report good experience using this dynamic split method:
https://cofounderslab.com/discuss/has-anyone-used-the-slicin...
With that said, I am sure there are a lot of different methods that could work depending on the people involved, it's not as if there is only one "right" way to do it.