I've heard about that technique in youtube, I think I'm gonna use it with pine, which is the only soft wood I have... I also have some remains of alder, let's see... what I don't have is leather.
I went to the shop and bought a 2 sided stone (fine and hard, still not sure which side is fine and which one is hard) and that white past for polishing... there were other colors, like blue or green, but since you were talking about that white stuff, I got it... the labels are in german, so I really don't understand where's the difference... both thingees cost 4 euros, so I think it was a good investment.
And these are the two gouges I have. The good one (in the right) is already sharp, made the arm haircut test, but still not a razor blade, so I will strop it before using it.
Here, the angle is in the inner side, which I think it will be a pain in the ass if I have to give it a heavy sharp some day... maybe with sandpaper?
The one in the left is a cheap gouge I bought long time ago and never used. I've realized that it has a bite in the edge. Luckily, this one has the angle in the outer side so I think it won't be a problem to get a sharp edge back with the stone... and the inner side with sandpaper?
Thanks for all the info, it's really appreciated.