Look for anything that harms your inspiration, for example, very many beginners fall into the trap of trying too many different methods at the same time or being too impatient. Get in the habit of sticking with a strategy, or finishing a project, until you have mastered it to a level of competence. Leaving projects incomplete just because you aren't seeing instant results is definitely not what you should be doing because this tends to leave open loops, and these open loops keep nagging you in the back of your mind that you've failed. So always focus on getting things done once you start with them, if you fail or succeed with the project is a completely different thing.
Work on your mind as much as possible because you need to develop mental resilience so you can withstand the hardships and tough days. You will not always have good days, as we all know very well, and so when that happens it will not sidetrack you. The real key is self-awareness because you will feel when things are beginning to get too much, and it is then that you have to muster that extra strength. Now you have a few strategies and ideas that you can work toward and bring them into your own way of thinking.
There really is something to the notion about time and the right time for all things that come to pass. When your time is not right for moving on something, then take note of it but avoid letting it become a source of excuses. Usually if not always, there seems to be a conspiracy working on your behalf when the time is perfect for something to happen. You'll have to wait for that inner voice to guide you when it comes to choose your timing.
Once you are able to take care of your mental state and motivation, you will simply become stronger at doing it. But also realize that this is only a small part of it because there is a whole industry devoted to motivation. The most important thing that you need to remember here is that motivation works well only when it's ongoing - so make sure you're consistently motivating yourself to make it big with Internet marketing.