Gmail filters are an easy way to manage your mail based on a set of criteria. Filters can be created to label, archive, star, forward or delete messages.
By using filters in tandem with labels you can create an organized, stream-lined workflow.
Labels help you organize your messages into categories -- courses, sports, memos, whatever you want. Labels function much like folders do, but with labels you can add more than one to a message.
Your system is that, YOUR system, so how I do things isn’t how you need or should, but your own system of organization should grow out of how you use the tool and how you work.