The absolute core fundamental skill that separates the elite from the casuals is the ability to perfectly track the opponent's elixir.

Playing the game without knowing how much elixir your opponent has is like playing poker without looking at the cards on the table.
The Economy of Aggression
However, if you launch that exact same 8-elixir push when you know the opponent has only 2 elixir, it is mathematically impossible for them to stop it.

You create an advantage by making positive defensive trades (e.g. If you're ready to see more info on tower rush stop by our own site. , using a 3-elixir Arrows to kill a 5-elixir Minion Horde).
Counting elixir tells you if they can afford their heavy spell.If they are at zero, they cannot immediately punish your 6-elixir Elixir Collector investment.It prevents 'over-defending'. How to Train the Skill
Start by simply categorizing the opponent into three states: 'High Elixir' (7-10), 'Medium Elixir' (4-6), and 'Low Elixir' (0-3).

Eventually, this process will become completely automatic; you will instinctively 'feel' their elixir bar without having to consciously calculate the numbers.
Resource LevelWhat You Must DoYou have a massive Elixir Advantage (+4)Immediate, overwhelming aggression; punish their lack of resources before they can regenerateYou have a massive Elixir Deficit (-4)Immediate, flawless defense; sacrifice tower health if necessary to regain economic parity; do NOT attack Mastering the Economy
Tower health is a deceptive metric; you can have full tower health and still be losing the game if you are down 5 elixir.

Knowledge is power.