First sand all the wooden parts a little if necessary. If necessary, also sand the holes a little to make the test tubes fit better in the openings later.
Then you can combine different towers from the different coils as you like and glue them together with the craft glue. Now you can put the test tubes into the corresponding towers.
Since different materials have been combined, it is important to first treat everything with a universal primer. This ensures that the spray paint covers and adheres evenly in the next step.
Also prime the flowers first and only colour them in the next step.
Finally, all you need to do is decorate everything nicely and your wooden spool tray is ready.