I am sure that there are more then 5 ways of making flowers, but this is my classification (kind of!). This is NOT a tutorial!
Today I will write about the simplest one, I call it "Circle".
Usually this is a first try to many new felters and very straightforward. The wool is placed in circle evenly (as you can manage!):

After usual routine (soapy water and rubbing) you get something like this:

Use a scissors to form the petals and start fulling:

And eventually you will get finished flower. I tried to make a courgette flower using a new (for me) wool. I am quite happy with the result, especially with the stem attached!