What are the most effective uses/tips to become an Instructional Designer?

I won't go into the academic qualifications you should pursue; you can google that. Here are 8 suggestions. They stem from an imagined “good Instructional Designer” persona that I have on my mind.

1. Do an awful lot of digital learning of your own. Then, think: what kind of learning experience do you find rewarding? That's the one you should aim to create.
2. Train people face-to-face. It'll expose you to situations you don't learn about at university, and it'll keep you focused on learners. Speaking of which,
3. Focus on the learner (and educate your clients to do so, too). Project stakeholders (i.e. your clients) will often drift towards Instructional Design that makes things easy for the course manager and the trainer or teacher, forgetting that the intended beneficiary of any eLearning project must be the trainee. You must alert them to this error, and gain their sponsorship for a more learner-centered approach.
4. Be extremely tech-savvy. Goes without saying that deep familiarity with learning technology is a must; but go beyond this, and be well-informed about technology overall.
5. Play video games. You'll learn a lot about things like guided onboarding and habit-building. What makes you intrinsically motivated to keep at it? If you don't find it interesting, what would you change to make it interesting? Write your answers down. How do your conclusions relate to motivating trainees?
6. Don't forget about business goals. It's wonderful when learning happens for its own sake, but training initiatives have one or more business goals behind them. First of all, make sure you know these (amazing how many of us don't ask), then make sure your design is geared towards them. (No, this doesn't mean you have to compromise your learner focus.)
7. Be budget-conscious. Be aware of project resources and timelines, and design learning experiences that can actually happen within your budget. (However, always tell your client what could happen if resources and time were more plentiful.)
8. Motivate, motivate, motivate! If you were to go away remembering one of these points only, this one should be it. Design learning experiences that users love and want to keep coming back to. Watch Dan Pink on motivation and Dan Ariely on what makes us feel good about our work.