I am a self-taught professional software developer with no post-secondary education. People get amazed and inspired by the fact that I learn programming "on my own" via the Internet and self-study. I use quotes because nobody learns on their own, the resources I use are made by other people.
Below is a framework for developing a positive mindset for self-learning. I will discuss other factors later but a positive mindset is the essential foundation.
Trust yourself. Trust that you have the necessary discipline, tenancity, motivation, interest, and energy to be a self-learner.
Trust that the educational materials you choose are good enough. You cannot assess what the best, most efficient, magic-potion learning resources are because you don't know what you don't know. It is more important to start than to optimize how great your start will be.
Everything is a work in progress. Your learning journey will not be perfect. If you accept and trust these statements then you will avoid analysis paralysis. Analysis paralysis is very real and it affects all skill levels.
Learning on your own will always look risky if you do not trust and believe in yourself. You are the teacher, you set the goals, curriculum, pace, and you know the truth at every step of the process.
Therefore if you do not trust yourself then you do not trust your leader to lead you to success.
Your friends and family will be skeptical because they are likely used to the assumed security of institutional education.
It is what they know and it is what has been expected and championed for generations. People trust institutional education because they percieve an expected, established outcome; put X in, get Y out, guaranteed (contractually).
If given the choice most people would choose to attend Stanford vs self-learn. Accept that self-learning may look more risky to those around you. Your loved ones naturally want the best for you so they will tend to pick things that look safe and guaranteed. This is ok. Things are ok. There is no right/wrong best answer.
The way what you do looks to other people does not have to be a significant motivating factor.
The fear of doing "the wrong thing" may dictate your life and your choices.
Doubt exists when you are not experienced in trusting yourself. Doubt combined with social pressure causes risk-aversion to the point you prioritize not making a wrong move that will look bad, rather than thinking forward with a positive mindset about your goals and objectives.
Accept that your journey will not be perfect. You will make mistakes. You will learn inefficient things.
Fear of failure is nonsensical because failure is essential in a learning environment and most usually yields the most valuable lessons.
Self-learning is very isolating and lonely.
Institutional education has the benefit of providing an automatic social network which includes both peers and professors. The feeling of having people beside you is very important and a very real, human desire.
This support infrastructure is not automatically included in your self learning journey -- you have to build it manually.
Fortunately there are many outlets you can use to build connections with people. Some examples are:
Manually building your social network is harder but it is a very useful skill that gets easier with practice.
Self-motivation is easy if you train yourself to love the journey of discovery, learning, and creating.
Do a thing because you get inherent satisfaction from doing that thing.
Avoid complexity and simplify your purpose. Simplicity of purpose makes it easier to obtain happiness and motivation each day, every day.
Learning takes long-term commitment, discipline and resolve. If you don't enjoy the process, chances are you won't stick with it over the long term.
It is good to have long-term goals but if you are only concerned with the end result you risk sabotaging your motivation during the long and grinding process of getting there.
Be motivated by each day of progress and discovery. Sometimes progress is masked as a setback -- that's ok.
Motivation is all about the long term sustainability of your energy so deriving happiness from the day-to-day journey is essential.
"keep your head up" is advice common in sports that has to do with being acutely aware of your surroundings and the state of the game.
Awareness is good in that it allows you to gain perspective and learn from external sources.
Being too aware of what is going on around you causes distraction and tends to hurt motivation.
If everyone around you is seemingly doing better than you or "ahead" of you then discouragement and doubt set in.
Keep your head down and recognize that this is your journey. Measure yourself against yourself.
Your journey will not be perfect.
Everything is a work in progress.
The primary goal is to start and keep going, optimizations and efficiencies will come later.
Start small and derive happiness from each and every day.
Overconcern with end-goals will only sabotage today's motivation.
Do a thing because you love doing the thing.
Every day you do the thing will be a day of happiness.
Success will come, in one form or another.
Trust yourself =)
Thanks to Al Walworth for proofreading =)