To become an excellent ski-jumper, you will have to go on practicing as much as possible but this process will provide you slow but fruitful result.
Practise springing and the Ollie by making smaller jumps unless you are capable and confident enough for trying something larger jumps.
Always make sure to feel your shins which should be pushing against your ski boots as you take off from surface during springing.
Follow a strategy by watching the performance of your competitors so that you can assess how fast you need to perform and what changes you might need to make.
It's important that the goal must be precise and you should not only focus on those areas where you want the improvement but also to cross-check if it is measurable and doable.
Analysis on the strength and weakness will be done simultaneously. Find your weak points and have a brief talk with your coach so as to erase or develop it soon. For example, if you want to compete in Olympic or world cup level, then you should be more serious about your timing, control in air, and landings etc.
It is a sport which requires a core leg power, hence one should do core exercises such as sprinting, skiing, and various core strength exercises to increase the back strength etc. Stretch your lower and upper part of your body thrice in a week to make your body more elastic.