It's not about "Fast", it's about not saturating yourself and focussing on the niche you're good at.
Don't oversell yourself, fill the time you have. When you start time is your friend. Once you're specialized you do not have time and you have to start saying no to things.
Finding the balance between who to contact where and why, and how often. Compare it to trying to be a landscaper targeting a whole city and advertising everywhere. You will be driving left to right, wear and tear on equipment and car will wear out faster, and you spend too much time travelling that you could be helping someone. And you probably want to stay cheap to try and get customers fast. VERSUS, picking one particular neighbourhood with the type of customer you want (the right type of overgrown lawns) and only targeting them. You have less to travel, your car wears out less quick. You can charge more per customer and you can cherry pick who to help when.
The same goes for online. Once you grow you can scale out and delegate tasks, outsource tasks. Hire staff, and take on more 'neighbourhoods'.