Hello joão,
We are not really a promotion organization but we do try to talk about
music promotion. Recently this list has been kind of quiet. However,
here are my tips and maybe others will have some insights.
One thing that can help is providing a translation to your description
(this will allow Google to find it more easily). You can also add both
English and Portuguese keywords...
You can see who is subscribe to your favorite YouTube musicians if
they allow you to view their subscriber list. You can send these
people invitations to view your music. Make sure to be polite and tell
them why you think they might like your music. Don't just say: "Hello,
here is my music. Please listen." Instead consider: "I found you while
searching for people who like soft guitar love songs. I thought you
might like this one..." And attach the video of choice. If you choose
well you will get many thank yous from people. Otherwise, you will get
many bad comments so be careful if you use this method.
You can also invite people as friends. YouTube doesn't like you to add
a lot of people at once or message too many people so it takes time.
There are many people that love to listen to music even from other
languages. It helps if you can do a short introduction to the song and
use video but it's not a necessity. The most important is that the
song is clear and the vocals are cleanly audible in the mix.
Doing cover songs can also get you some attention but there are legal
problems with that. I'm in the process right now of working out a deal
to do the Eagles song "Desperado" it takes time and a lot of creative
ideas. Most people that do cover songs on YouTube do so illegally.
Some have been banned for violating the law so I advise caution if you
chose this. If you are signing along with a karaoke track or the radio
that is usually considered legal - whereas doing your own version
requires special permission.
I wish you blessing on your tubing and welcome to the YouTube Music
Makers group. If you learn anything out side this group please come
back and share... Well be happy to learn from you too... I'll be
watching your progress...
...Rods ;-)