I was a real estate agent in Colorado for a few years, and here's my random thoughts if you're going to try and sell your house FSBO, based on my experiences with some FSBO sellers...
1. The MLS. My opinion is, the house MUST be in the MLS. I know some people have luck selling a house without it being in the MLS, but for the vast majority of home sales, buyers are either searching web sites like Realtor.com (which is really an MLS aggregation site), or they're using a buyer's agent who is searching the MLS. Either way, I'm a firm believer it MUST be in the MLS. That means you need to at least pay somebody to put it in there, such as a flat-fee broker who just lists it in the MLS.
2. Commissions. Many (most?) buyers use buyer's agents, and they (and their brokerages) expect a commission on the sale. On a "typical" 6% arrangement a seller has with their listing broker, that means half of that, or 3%, gets paid to the buyer's agent (actually, their brokerage in most cases). You might be able to get that lower depending on the market and your area. HOWEVER...don't be stingy with the buyer's agent's commission, because I can promise you buyer's agents won't even bother to show a home if a FSBO seller is being stingy. I remember some FSBO sellers in my area offering to pay 1% tops. After the brokerage gets their cut, plus the tax man, it wasn't even worth it to the agent, so we didn't even bother to show those homes.
3. Lockboxes. Regarding accessing the property for showings, agents have to show homes when their buyers are free, which isn't always convenient for a FSBO seller, especially if you work away from home during the day. Invest in some kind of lockbox so the buyer's agent can set up a showing and get into the property whenever their buyers want to see it. The easier you make it to show the home, the better. If you have all kinds of hoops to jump through to show it (such as only showing it at night after you get home from work), don't be surprised if you get no showings.
4. Showings. During a showing, don't hang around while the buyer tours the house. GET OUT! The buyers don't want the seller hanging over their shoulder while they tour a property and discuss all the things they do (and don't) like about it. Some FSBO sellers are really guilty of this one, hanging around to watch the buyer's reactions, or thinking they need to be there to answer questions. You don't - GET OUT! Leave, go walk down the street for 20 minutes, or whatever. If the buyers have questions, they'll relay them through their agent, and the agent will talk to you.
5. Paperwork. You either need to be very comfortable with legal documents, or hire a limited-service broker just to handle paperwork for you. Assuming the buyers are represented by an agent, that agent is going to submit offers on some kind of legal document (such as a state Department of Real Estate approved forms). If you happen to live in a part of the country where real estate attorneys are common, the contract might have been drafted by an attorney. State laws vary, and there are things in a real estate contract that COULD (however unlikely) come back to bite you. My advice would be to hire somebody to just do the paperwork, but it's still your responsibility to receive offers, counter them, accept them, decide on dates, etc.
6. Price. Take emotions out of it, do your homework on comps that have sold recently, and price your home realistically. I found FSBO sellers too emotionally attached to their homes, and overpriced them almost all the time. When we submitted offers on some of them that were lower and in line with recent sales, they'd get easily offended because they didn't have an agent in their corner explaining the rationale. If you don't get any showings, don't get any offers, or if the offers repeatedly come in low, you probably overpriced your home. Don't get emotionally offended by this.
That's all I can think of. Good luck with however you decide to sell it!