.  Selling art means becoming a business in-and-of yourself.  Now that you've built a small following, give your fans a place where they can learn more about you and your work. Use social media like Facebook or Twitter to link people back to your website.  This way, your followers will know you can always be contacted at this place regardless of what online trends come and go. Now that you've sold or showcased your work, establish a means of maintaining communication with important art folk.  Your database of supporters and investors can be your most powerful marketing tool.  Make sure you have ways to inform them of your upcoming exhibitions.  Acquire phone numbers, email addresses, and mailing addresses as well.  Avoid selling your art through other channels if you have already worked out a deal with an art gallery.  Many art galleries are hesitant to even share their contact info in the first place because they fear that artists will sell behind their backs.  Be persistent when attempting to contact new prospects.  It may take many attempts before you find someone willing to sell your art. of all your local contacts and customers.  Every time you make new artwork or hold an exhibition, notify your mailing list.  Be sure you ask for permission to contact to your clientele.  You want to provide them with meaningful updates, not unwanted spam. Contact customers personally whenever you have new artworks available, or when someone has bought a piece from you.  Send letters expressing gratitude for purchasing your art.  Remember, someone who has bought your art has expressed sincere interest and has made an investment in you.  Failing to maintain contact with customers beyond the first transaction can come off as rude and dismissive. Once you've got a steady following, determine who the constant supporters are among your fans.  Offer them special treatment like opportunities to connect with you and first shots at purchasing your work.  If you paint murals, offer a small, free portrait of your fan's face.  If you...

TL;DR in Indonesian:
Mendaftarlah di situs web atau blog di domain Anda sendiri. Dapatkan nama dan info kontak dari semua pendukung Anda. Buat sebuah daftar milis berisi kontak lokal dan pelanggan Anda. Sering berikan perlakuan dan manfaat khusus pada pendukung Anda. Sering siapkan janji makan siang atau makan malam dengan prospek yang potensial maupun yang sudah ada.