i dunno why, but i can't save anything 0_O' . . .
when i open the "edit skin", the save button disappears . . . 
That sounds more like a technical issue you might have to take up with Deviantart. I've never seen that before.
i have some account . . . and in all that doesn't work. i don't think that it's a technical problem because i have waited one month to try again, and it's still like that. . . : /
Do you pay for a subscription?
no
i have to do it ?
i have to do it ?
Yes, in order to customize your journal you need to have a payed subscription to DeviantArt.
that means that i have to be premium ? 0.O
Yes it does.