You can look to attract clients by offering a deal. Online advertising lets you target your ads with user data specifically like choosing the age, gender, location, and the occupation. In case there are discounts or deals that you are offering, then online ads are the best way to promote your business.
Big brand names like Facebook and Google offer an excellent platform that gives you targeting options, but you may also wish to target other blogs and site which may be recommended if you work only for a special niche. Referral programs work wonders where you offer rewards to those who promote you. You give an extra bit of incentive to those who refer you to family and friends and thus help grow your business.