1. non-concrete: understanding what is possible in daytrading and what is not. which problem has solution, which hasn't. 2. concrete: the average trade should be not more than 4 ticks. This makes impossible to trade size bigger than average size on DOM so no competition with big boys. For example, the strategy with 10 ticks or so stop and 20 ticks or so target and 40% win rate is realistic one and produce +2 ticks on average. Very realistic for CL market (average size 30+ contracts on DOM) and FGBL (average size 200+ contracts on DOM). If you are small behave like small and do not waste time for creation the strategy with tens ticks stop/profit.
Probably the best advice I ever read was from Peter Lynch, trade in what you understand. Doing that never really failed me whereas the biggest fiascos were always stuff I didn't really get from the word go. Regarding this advice: "Always have a plan, for better or worse. A man without a plan is destined to lose." - My father. Good advice but remember Napoleon's advice as well: "No plan survives contact with the enemy."
Analogous to this, to paraphrase Mike Tyson (yes I know): "Everybody has a plan until they get punched in the face."
I agree also, but this is such a hard pill to swallow for millennial's and other people who are so used to finding out everything that they need by going on google. We kind of lost the "art" of figuring things out by yourself through trial and error.