When helpful: When you want to increase visibility and awareness of your products / services, display advertising is a cost- effective option. As you pay for cost per Millie (cost per thousand impressions), instead of cost per click.
Create your ad banners as per IAB ad formats and creative guidelines. For example, create 300 x 250 px, 600 x 160 px, 728 x 90 px, and 320 x 50 px for mobile devices. Use graphics, images, and rich media to make ad banner visually appealing. Hire a professional designer if needed.
Pricing: Decide your cpm (cost per Millie) ad rates for your display ads by considering prices of your product / services, your margins, current conversion rates, geographical area where you want to display ads and its position on the web page, ad size and popularity of a particular website. Consult with ad agency about your ad pricing and then launch your ad campaign.
Average cpm rates ranges from as low as .30$ to average of 2-3$ and as high as 5-8$.
Display ad rates vary according to region. For example, for U.S., Canada, Europe, Australia cpm rates are high compared to the rest of the world. As these are more evolved markets for web advertising and per capita income and consumer spending is high in these countries so are the ad rates.
Also ads placed above the fold of a web page costs more than ads placed below the fold.
Launching your web display ad campaign: Sign up with a good web display ad agency, fix your ad campaign budget, check their payment terms and submit your ad to ad network. Once they approve your ad, your ad will start showing up on their network of sites.