The following is only MY OPINION of instructing.
To be comfortable as an instructor, I believe that you need to be very experienced [ie 5+ years of constant flying]. I know a lot of Instructors who will disagree, - fine.
As an 18 year old, you do not have the experience to talk the truth under pressure while flying accurately and providing confidence to another trainee pilot.
I am first to acknowledge that as a 38 year old, I cannot fully relate to an 18 year old student, and therefore you may, but after 20 odd years of flying I can admit that I am still learning.
Instructing is relating 50% experience 50% books/syllabus, while always striving for 100% accuracy.
You may be a good pilot - develop that further.
Good luck......