So In conclusion, I respectfully ask "what is your Effective Expert Advise for a Person (me) that has enough Salary but still want more Financial Stability using cryptocurrency".
No salary is enough, it's in the future after retirement you will understand this most important if you are such that likes to enjoy the good things in life. However, it's an opportunity for you to earn more and use the good salary to your advantage as the money invested is not a waste, this is particularly if invested rightly and wisely.
I believe the job that is earning you that big salary will surely be demanding as well, nothing goes for free. This is why I know that you might not be able to get involved in some direct businesses, yet, the following should do well to help you earn more;
1. Investment in Cryptocurrency
2. Land and Real estate
3. Treasury Bills and Government securities
4. Partnering companies with a guaranteed annual percentage return
5. Buying of Shares
6. Oil & Gold ETFs
By the way, this is general advice, DYOR and be sure to learn what you committing your asset to. As you can see, these are both online and offline dealings and this is how best the investment life of everyone should be, you mix them in case.
Specifically on Cryptocurrency as you requested, invest in Bitcoin and some alternative coins too. A bull run is coming where multiple earnings on crypto investments would be made, so you might want to get started now. But please, read your eyes on cryptocurrency before you commit your money. You might want to read for;
1. The best wallets
2. Payments (Buy & Sell)
3. Privacy and Security.