I used Sweets and Beyond as a guide for making Sazon. You should go check out her channel on YouTube. You can see how much color dyes are in the store-bought Sazon.
This is what we did for our home-made Sazon.
Ingredients 
1 1/2 tsp cumin
1 1/2 tsp dried oregano
1 1/2 tsp garlic powder
1 1/2 tsp dried cilantro flakes
1 tbsp Annatto (or Achiote)
1 1/2 tsp ground coriander
1 1/2 tsp salt
Measure all ingredients and put into a spice grinder and grind this mixture until it turns into granules. Once all the spices are gridded put into a container for daily use.
We did taste the store-bought brand verse our home-made and you can taste the difference in freshness and salt. After the seasonings are gridded you can see the similarities.
Note: we did add some salt to this and it really enhance the other spices.