This is a timeline of things that will need to be done, and approximate dates when you should do them. I hope it is helpful.
March/April - At conference during the year PRECEDING your own, check out the chosen conference date with officers. Be sure as well that the date does not conflict with CACW's, since there are folks who would like to attend both.
September - Figure out who your keynote speaker is going to be and how you are going to pay for that. Sometimes you can piggyback on a speaker who is going to be coming anyway, or apply for a university mini-grant to bring somebody. This may affect the date of the conference, or it may not.
October - Find a place to hold your conference. You might use your university's regular lecture halls, or perhaps the university's conference center. For Friday night or Saturday midday, or whatever you choose, you need a place to hold a banquet for about fifty people.
For Saturday, you will want two rooms each seating about 40 people for the talks, and a hallway or something outside the rooms to set up literature tables and snacks. You'll also need a room for the lunch, and someone to cater the lunch and the snacks. CAPN Bulletin 37.2 has a useful breakdown of a sample budget.
January - Send a reminder call for papers at the beginning of the month, just before the deadline. Then when you have all the abstracts, separate them from the names and go through them (I found this easier to do with a partner) and decide which ones to accept. For guidelines on which papers to accept, ask any recent President.
February - Send out acceptance emails to the people whose abstracts were accepted and nice emails to the people whose abstracts were declined. If you don't hear back from someone, you might want to follow up to make sure they got your email. About the same time, make a web page telling how to register for the conference, what it will cost, and how to get a hotel room. Email the webmaster to link to your page from the main CAPN website, or the webmaster can create the page for you from an email.
When creating a registration form, be sure to specify meal type (meat/vegetarian/vegan/food allergies) - or have a buffet - and include a reminder that all conference speakers MUST be a member of CAPN (and thus must update their membership, if they haven't done so recently).
March - Organize a group of volunteers to put together a packet for the conference attendees. The packet consists of a large manila envelope containing (for instance) a copy of the program, tickets for the banquet and for lunch, maps of how to get to the talks and the hotels, maps of the town, and tourist brochures for what to do in your town.
April - Organize a group of volunteers to help you on the day of the conference greeting people, registering people, running errands, and so on. Be sure that you have someone on hand who can help with the AV equipment, should there be any problems, bearing in mind that at many universities the AV people take the weekend off!