As with any skill, writing is learned by practice! So, consider this: every time you write something, you get a little better! :-)
Here are some editing tips for you:
That means we should not only save our money without using it or we just enjoy it without saving. - This sentence is unclear. Better would be: This means we should neither save all our money nor spend all of it; we should strike a balance between the two.
I can't imagine how hard my life will be if I just spend a little part of my money for all things in my life. - I'm not sure what you were trying to say here; it's not clear.
Every day we work hard to earn a lot of money but if we do not use it to make our lives better, the value of our hard word is not compensated meritoriously.
Both enjoying our money when we earn it and saving it for long term goals in the future have advantages and disadvantages [delete "of each"].
We should not use it up immediately and we should not only save all of it without using it comfortably and effeciently.- You should delete this sentence; it is repetitive.
furthermore, money will be the key factor for my prospect of life. - I'm not sure what you meant by "prospect of life." Perhaps you meant "Money will be a key factor in my success in life"
I believe we should use it suitably, not so little and not use it up any time. - This is not very grammatical; better would be "not squander it thoughtlessly, nor horde it like a miser. The best solution is usually a balanced one."
I hope this helps!