After spending some time looking for a promising investment. I decided to go with Polkadot (DOT) and stake it for 30 days in BINANCE in Locked Stacking because the "APY" interests were quite high (approximately 17% at that time) and the project itself was very promising.
I have to add that I did everything from the same binance, so it is important to have a binance account. I am attaching my referral link in case someone still does not have a binance account in 2021:
!! MY BINANCE REFERRAL LINK !!
1. BUYING POLKADOT
First step was obviously to buy some DOT. At that time the minimum DOT amount that Binance requested for Staking was 10 DOT. So the fifteenth of February I bought around 400 Euros (485$ aprox.) worth in DOT. That turned out to be 16,983 DOT.
2. PUTTING DOT TO WORK
To stake my DOT was very simple, from the binance interface: FINANCE / BINANCE EARN
Once inside, we scroll down until we find FIXED TERMS / STAKING and we click on VIEW MORE
There we can find all the Locked Staking options that binance offers. We will search for Polkadot (DOT) and choose our plan for 30, 60 or 90 days. (the longer the time locked, the greater the interest). I attach the interests that binance is offering right now in each plan: 
I must add that right now the 3 plans are almost always sold out and you have to have a bit of luck to be able to put your DOTs in staking.
This is a good sign since it indicates that the community believes in the project and sees it as a good investment opportunity.
3. RESULTS
Finally and the most interesting part and for which most will have entered the post, the result, how much have I earned after 30 days locking my DOT in Binance? First the DOT price has increased in these 30 days, when I bought it, it was about $ 26 for each DOT and when writting this the prize is 37.38$ resulting in a profit of 43.28%. In other words just for holding my initial 16.983 DOT I made 193.67$ PROFIT
But that is not the end, remember that I staked those 16.983 so how much did I made by staking? After 30 days I earned 0.21 DOT in interests, equivalent to 7,86 $ right now.
4. CONCLUSION
Not gonna lie, was hoping to win something more for Staking. But even so I think it is a good opportunity to get passive income and I trust that Polkadot will play a good role in the medium / long term so today I staked my 16,983 plus earnings again. Let me know your opinion in the comments section and forgive me for my poor level of English. Thanks for reading my first post and hope to be back in 30 days with the results of another 30 days journey of staking DOT in Binance.
