Instruction For Seborrhea Treatment How Can I Make An "instruction Manual" For Work?

How can I make an "instruction manual" for work? - instruction for seborrhea treatment

Our office has received are very few new employees, and there's more to come. It is very important that people stand in line with the procedures. Someone suggested to keep a book / manual, to new people. It would be necessary to clarify procedures and information about how we use it and when we use it. We need suggestions on how to do it effectively and clearly. I do not know where to start. There are many details to work and do not really want to write a novel.