To make money online with data entry, start by reaching out to past clients for new projects. You can also ask friends and acquaintances for referrals. Platforms like Upwork, Mechanical Turk, and Virtual Vocations are great places to find data entry opportunities. Additionally, utilize social media, local chambers of commerce, and cold outreach methods to find clients online. Understand your target market, create a business plan, and develop an effective marketing strategy to start your own data entry business.