Hello,

This is the story of my life, man. You can take a look at a piece Peter Drucker (the "Father of Management") wrote, for the Harvard Business Review, titled "Managing Oneself". Here's an excerpt:

"""
We all have a vast number of areas in which we have no talent or skill and little chance of becoming even mediocre. In those areas a person - and especially a knowledge worker- should not take on work, jobs, and assignments. One should waste as little effort as possible on improving areas of low competence. It takes far more energy and work to improve from incompetence to mediocrity than it takes to improve from first-rate performance to excellence. And yet most people - especially most teachers and most organizations - concentrate on making incompetent performers into mediocre ones. Energy, resources, and time should go instead to making a competent person into a star performer.
"""

You can also take a look at David Allen's "Getting Things Done".

I found that the problems you are talking about, for me, have stemmed from poor time management. I didn't know where time went, and I would do/study something, neglecting another thing and then recalling that it's been ages I haven't looked at the darn thing and completely forgot it. So...

So it's not visiting something for a while that screws things up. I needed to make sure that I visit everything at least once a week and make it constant. Not ignore it for a year and then try to get back to it.

Naturally, you can't do everything daily..

I studied Electronics Engineering and I graduated few months ago. I organize my time (think "Country/State budget", finite) into 4 axes(think "Departments"). I assume it's a 16 hour waking time. Each "Department" gets a specific "budget/time"

Axes/Departments: Engineering (9 hours), Business (3hours), Lifestyle (2hours), Culture(2h).

These are the core of who I am/want to be.

- Engineering:

* Reservoir Engineering/Characterisation (General + specific: NMR, sonic, induction logging, etc).

* Electronics Engineering.

* Physics (Landau & Lifschitz, Feynman Lectures, Atomic/Nuclear).

* Mathematics (Old college courses : Piskounov, Demidovich. New ones: Kolmogorov).

* Brush up my rational mechanics (well, basically stuff we did in college in the engineering course).

* Signal Processing (Oppenheim, etc).

* Programming: (Python, currently building an application). C (for microcontrollers and much more). Erlang (because I want to). In addition to the stuff I'm using.
*
- Lifestyle: Fitness, time with family and friends: Because I found out I was neglecting my loved ones in my quest.

- Culture/Self improvement:

* Short term goal: Fluent in the 6 official U.N languages (3 down, 1 on in progress). Then German.

* Learning how to draw and paint, learn to read music and play guitar.

* Literature (raised with French literature classics, touched a bit of Russian, keeping that going).

* Raised in the military, so I'm interested in weaponery and intelligence.

- Business:

* Economics 101.
* Management.
* Business.

I divide each day in 16 slots, I have a spreadsheet with colored blocks(each "axis/department" has a color) and make sure I touch everyone of those aspects multiple times a week.

So I may skip today's session of something, but I make it up the next day.

Many of these may not "bring" something or advance my "career", but the scope of all of this is a lifetime. For me, it'd be a shame to die being completely clueless in Physics or saying something "I forgot how we went from Green and Stokes to Ostrogradsky".. I want to be able to say on my death bed that I died an Engineer.

I'm 27 now, completely ignorant, without talent, but a stubborn motherfucker. It also help I'm addicted to reading and find it satisfying on its own.