Yes, this title is a little mercenary, but that's what freelancers are. Mercenaries. We just don't use lances these days (except for freelance Renaissance Faire lancers). We use pens and laptops and video cameras. The being self-employed thing means that sometimes we have to get a bit creative in order to do certain things.

For example, say that you want or need to travel to a work-related conference. For one thing, keep all of your receipts, if it's related to work you can probably write off the conference fee, the hotel, the travel, related tips, and meals. But on top of that, see if you can find a way to create work out of the trip. Since I write a lot of articles, I like to see if I can cover the conference for one of my usual publications. Getting paid to write about the conference lets me recoup some of the costs of attending (and attending as media covering the conference can reduce the cost of getting in, but please don't try to do this unless you really are covering the show or you'll make it harder for the legit folks later). 

Another thing to do is to see who else you do business with is going to be at the show. If there are particular people you like to track, consider signing up for a site like TripIt, where you can load up information about the trips you're planning and invite colleagues and friends and family to do so as well (TripIt also can integrate with LinkedIn if you happen to use that site as well). This type of "trip networking" site lets you see when you and someone of interest are going to be in the same area at the same time, and makes it easier to plan meetings or fun side trips. Even if you're not doing a project now with someone else who will be there, connecting with them even for a few minutes over an over-priced conference cafe coffee is a good way to nurture the relationship that can be so important to future work together. It's easy to forget these days how valuable "face time" can be, but it really can help.

Then there's finding new work. If the conference has anyone that might be a source of work for you, print up some business cards (and please make them nice and professional, not those tear-off things that leave little bumpy perforated marks along all the edges) and work the floor. Again, since a lot of what I do is writing, I typically take the time to say hi to most of the publications represented at the conference. Since I also write books, if I have a book that's current I also notify my publisher that I'll be there and find out if they'll have a booth and are doing signings. 

Another thing about attending work-related conferences. If you're at all planning on seeing clients and trying to land new ones, look the part (I know, said by a person who is not exactly a fashion maven). That doesn't mean that you absolutely must wear a suit. In fact, at some conferences people will assume you must be with marketing if you do--at many tech conferences most of the geek class wear jeans and t-shirts. But keep in mind that you want to make a good impression and dress accordingly, even if that just means leaving your rattier jeans at home.

Aside from dressing, there's one more thing that should be mentioned in any article about attending conferences: comfortable shoes. The bigger the show venue, the more comfortable the shoes need to be. I cannot stress this enough. Some people even recommend bringing two very different pairs of shoes and switching them in the middle of the day, but frankly I'm never that organized. 

Why harp on shoes here? Sure, ratty shoes can also make a bad impression. But the real issue is that if your feet are absolutely killing you, you're not going to be very personable, and may not make a very good impression. Not only that, but you may also decide against meeting all of the people you intended to meet just so you can go whimper in peace in your hotel room, wasting an otherwise good chance at connecting with people who could lead to excellent projects later. And, who knows, become good friends.