Independent contractors are essentially a small business with one employee - yourself. For that reason, you need to follow all of the same accounting principles as any other small business. The good news is: it also means that any accounting tips and tricks for "small businesses" can be applied to your independent contracting business.
Especially if you're just starting out as a freelance IT professional in the gig economy, the accounting side of the business can be intimidating. To help ease the stress, check out this video from Patriot Software that runs through some basic accounting tips for small businesses.
If you're still unsure about these tasks, we strongly recommend you engage a professional accountant. Avoiding tax complications and properly planning your finances will be well worth the money you pay.