The website http://www.artmarketing.com edits plenty of books. It's all about helping artists empower themselves. Althouthg it applies mostly to classic marketing, we may transfer the principles to online marketing.
Here are the 5 factors to success they mention.
1- Continually contact people
This advice aims at expanding your network and word-to-mouth buzz. Use the phone, emails, Facebook, Twitter or whatever mean at your disposal to continually stay in touch with the ones interested in your work.
2- Follow up
After any mailing action for any announcement (exhibition, new features on your website,...), whether it is per email or postal mail, don't forget to follow up even if your received a rejection. Considering that you mailing list will never be huge (most artists have between 100 and 500 contacts), it is necessary you spend time on this task as you must contact people several times to get a response.
3- Use innovative marketing
Try new stuff and think out of the box. Don't be afraid to experiment new exhibition places, new communication media and techniques. Whatever goes through your mind.
4- Press coverage
Successful artists get good press coverage, which helps their notoriety. So never neglect this aspect of communication and regularly send the local press, the specialized press, the online press, information about your work and agenda.
5- Long-term goals
You got to stay focussed on your long-term goals: becoming successful. It doesn't happend overnight. You have got to plan and strategize your work. And never give up.
Check this related post: http://reproduction-tableaux.typepad.com/art/2010/05/10-conseils-aux-artistes-contemporains.html
Source: http://artmarketing.com/5factorsto%20success.html
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