"The companies that benefit most from going public have strong and sustainable earnings growth or large quick gowth potentiall. Also having a proprietary technology, product or service will put you in a stronger position than other companies. You also need a stable, strong management management team . And of course you should have strong internal controls and systems to handle increased growth and timely financial reporting. The main reason that companies go public is to raise cash. The newly raised funds are used to finance growing operations, pay off debt, buy another company or launch big advertising campaigns.
An Initial Public Offering (IPO) can reward the company's early investors and employees by creating a market for the company's stock."

http://www.rfb.lv/public/pakalpojumi/40963.html

Ways how to float a company
just list on the secondary market. The liquidity of company shares increases; the present shareholders are able to buy and sell shares at market price; the company shareholder base is expected to expand;
company may do an IPO, raising money for development or project financing.;
the present company shareholders sell a part of their holding.