Gallery representation can be tricky but I've also found that it can lead to some of the best symbiotic relationships both as an artist and as a human being. I totally believe that my greatest successes come from working in community with others and the artist/gallery relationship is one of those collaborations.
Initially, when I began exhibiting publicly I was under the impression that once you had gallery representation that was it, you hit the big time as an artist. It didn't take long to realize that even if you are connected to and believe in what you create and a gallery director feels the same, the general public, or the clients they represent may not feel the same. I have also learned that spending money on marketing and exhibition space probably won't solve this problem, it will just cost you money. So I always advise artists not to invest whatever they're not comfortable letting go of.
At the same time, I really do believe that if you are committed to what you do, and believe in it, love it whole-heartedly, there are others out there who will love it, too. And, looking around at all the arts, really at everything that we do as people in this world, there is never a time to sit back and revel in the never-ending rewards. The amount of time and effort that is put into the work will be reaped somehow at some point.
If you are interested in gallery representation, here is a little advice that I wish I would have received early on in my career...
Visit the space (or if it is far away, visit the online space). Your work should fit but not compete with the rest of the work in the venue. For example, my work consists of contemporary acrylics on stretched and unframed canvas so I wouldn't contact a gallery that deals in photography, printmaking or traditional framed works.
Get to know the director and staff. Do they speak your language? Do they connect with the art and artists the way you'd like? Do they represent their artists the way you would want to be represented? If all goes well this could be a long-term relationship so you should be able to communicate well. I consider the directors and staff of the galleries I have the privilege of working with as friends...really, really great, inspiring, lovely friends.
Introduce yourself and your work to the gallery. Be professional and succinct but be yourself. Take into consideration that they are busy and are contacted my numerous artists but also remember that this is a two-sided relationship. You are interviewing the gallery as much as they are interviewing you.
Remember that it takes two (or more) to accomplish great things. Don't expect the gallery to do all the work...share information about them as much as they share information about you. Not just about your exhibit, but also about the other artists they represent. I totally believe in karma, whatever you put out there eventually comes back. If my work isn't the right fit for someone, perhaps another artist whom I have the privilege of exhibiting with may just have the piece of someone's dreams.
Finally, trust your gut, your intuition. You'll know if this is a good fit for you. Also, trust that if it's not meant to be, there will be something for you out there...there always is.
Typically artists pay for shipping to a gallery and the gallery pays return shipping, but make sure to ask so that everyone is on the same page.
Once you have a commitment to exhibit your work, even in a public venue like a coffee shop, make sure to come prepared with all work wired and ready to hang. Don't take up too much time or space and be considerate and kind.