Xradar is right. Start to follow many people and ask them to follow you too. Use Facebook to get a bunch of followers. Then, if you already have a couple of followers, take time to tweet. I mean there are people who have twitter account but rarely use it. Lastly, don't just be interested with others. Be interesting.
Try to follow that followers who are just like your niche and business. Then they will automatically follow you. Also share your ideas, thoughts etc. with them then they will also do with you as well.
To get more followers you may use Twidium and Twiends. At Twiends you follow people and get seeds for it. Some followers start to follow you back.
For SEO-purposes, use TWIENDS... other than that, just update your account regularly and people will eventually follow you.
If you are using your twitter page for promotion of your website then follow these techniques, - Create a Twitter Landing Page as your “Webâ€URL - Distribute freebies to your top followers - Your user name should be related to your niche or to your brand - Follow people related to your niche and encourage people to follow your with your quality tweets - Do not tweet about anything that is happening around (like, Oh! Lord... Its raining) People usually do not respond to such tweets and you are stuffing irrelevant tweets on your own page... So, tweet regularly but focus on quality - Integrate 'follow me' button on your website - Create controversies (controversies attract more followers) - Follow other people and talk about your services and products