If you're just starting out, consider focusing only on two networks initially. For instance, if you plan to create a YouTube channel, start with a profile on Google+. Then slowly add another option later on. Remember, having a presence on multiple networks increases your chances of success. Plus, it makes it easier if something goes wrong since you won't have invested hours into a project already!
After making sure that you have started small and have developed a solid understanding of each network, set goals based on how many people will see your content and how much time you need to invest per day. If possible, aim to meet those numbers by completing tasks related to your networking efforts first thing in the morning instead of waiting until late afternoon. This way, you avoid spending too much time trying to squeeze everything in while still working full-time.
It's easy to fall prey to thinking that any old piece of content will do. But remember that not every shareable image or video needs to go viral. Instead, focus on creating high-quality content that offers useful information to potential customers. Make sure to keep track of things such as comments made on various platforms so that you know whether or not your audience responds positively to different kinds of content.
Once you feel comfortable with what you know and want to move forward, find an expert advisor who specializes in digital marketing. Someone like me could help guide you throughout the process, helping you choose which tools work best for your business, teaching you ways to increase engagement, and suggesting tactics to improve conversion rates. It might be worth paying more than $100/month to someone dedicated solely to learning about these platforms and helping others achieve similar successes, but there are plenty of free options available online. Just make sure whoever you hire has experience with Facebook ads specifically, otherwise he or she might miss key details when recommending strategies. And finally...
As you continue building your blog and following others on Twitter, you'll notice a few trends pop up over time. Some of these ideas will resonate well with your target market, especially if you pay attention to their feedback. Others will likely come across as boring and irrelevant. Either way, never stop listening to them and incorporating them into your overall plans.