If you know anything about authors, it's that we are flying by the seat of our pants. There are rules to follow, and guidance on genres and what works and what doesn't, but at the end of the day, you need to appeal to an audience. Take 50 Shades. I haven't read the book, but I've heard some terrible things about the writing, about the "fast and loose with the facts." But it reached an audience. Jane Eyre, a classic book which I love, isn't exactly the best written book, but the deep point of view grabs you, nonetheless.
I thought I'd share some of the answers I gave to the questions he asked.
1) best ways to advertise/make your book well known and how to sell it
Okay, let me start with know your market. Make sure you know the "rules" for that genre. Some genres provide more leeway than others in different areas. For instance, you may be familiar with the term "Info Dumping." When you write sci-fi, you are building a world, so you necessarily have to include more detail, more info. Dumping is still frowned upon, but the amount of information is necessary. In other genres, there are "As You Know Bob" details (most people are familiar, you don't need to spell it out). Bottom line, make sure the writing is strong and focused on the requirements for your market/genre.
Marketing is a challenge, especially right now. I'm hearing from all my indie author friends that sales are down across the board. With that being said, here are some of the things that have worked for me. There are book newsletters who will promote you, some of them fairly inexpensively and others for a bit more money. Fussy Librarian is a good one, and BargainBooksy/FreeBooksy. Bookbub is a bigger player in the field, but also costs quite a bit more to run with, and there are pre-requisites. A certain number of good reviews. In addition to the newsletters, pop around to "real world" places that might be relevant to your story. An example would be if your book featured a bed and breakfast. Organize an event at a bed and breakfast, or ask them to sell your books on consignment. It never hurts to contact your local bookstores, too. They like to help authors, although B&N is a little harder to get into these days. They often do local author nights, but the ones in my area are store by store (i.e., corporate B&N doesn't support the expense so much anymore). Blog tours are big, or Facebook parties. Find Facebook groups or book blogs. There are bunches of them that do group events and it's only a matter of signing up. The tricky part is to find readers, not just a bunch of authors pitching to each other (although authors are also readers). Lots of authors do blog tours. I recommend the tours.