Hi Fazzy, 
We aim to provide a great value way for artists to exhibit their work without being blocked by a selection process or charged commission.  It is all about giving back artists control over how they show their work.   With this in mind, we aim to be as open as possible with our artists and give you as much information as possible below.
Bigartspace Advertising
Bigartspace’s advertising strategy focuses on promoting the main Bigartspace galleries, which all artwork exhibited is displayed,  so your personal gallery will always get traffic from our advertising and promotion activities.   
Currently our advertising focuses on "Search Engine Optimisation",  which is a strategy to push Bigartspace high up in search results for certain phrases people search upon.   We also advertise heavily in a variety of online mediums.  Currently, you will spot Bigartspace at the top of search results when searching on Google for phrases like "buy art".    The mix of advertising both online and offline varies throughout the year.
An artist can also promote their own gallery.  Some tips are below.
How to encourage people to your gallery
The internet is a big place,  so the best policy is to go to a big popular site and tell other people about your gallery.    Always remember to provide a link to your personal gallery, then people will come and visit.   Also,  Search Engines will read these messages and then move your gallery higher up in their search results.   In general, the more links to your gallery across the internet the higher up in search results you go. 
A good place to subtly promote your site are sites like Yahoo Answers, where people ask questions about art  http://uk.answers.yahoo.com/    also Art specific forums on the internet are a great place to ask people to review your work.
Another trick with Search Engines is to make sure your gallery description, artwork description and artist biography are fully completed,  also try to encourage reviews.   Search Engines read this text and then work out for which search phrases you should appear.   So for example: 
If you wrote Fred is a fine artist born in Britain.  Fine Art has been her passion…      in your biography, then chances are a search engine will spot the references to fine art and fine artist.  Then when people search for “fine art” you will likely begin to appear in the search results.
So in general, the more links you have to your gallery from other web sites and the more complete the text on your artwork, gallery, biography and reviews.  The more likely you will receive higher levels of traffic.
How to get reviews
Reviews also help with search engines and encourage more people to buy.   The more text you have on a page, the more text a search engine can read and then classify your page.   
The best way to encourage reviews is to review someone else’s work that you like and ask them to review your artwork,   you could also ask a friend or colleague to leave a review of your work,  which should then encourage others to do the same.
I hope this helps with your choice of online gallery to join.  If you have any questions, feel free to leave a message here in the forum or send us a message via the Contact Us page
Kind Regards
Bigartspace