What do you do in your free time?
I like to read a very interesting book, to watch television, sometimes i´m going to disco.
I find reading books interesting, enjoy watching television and I sometimes go out clubbing.
These are varied activies, Majosa! Here are updates and comments:
I like to read a very interesting books, and to watch television. (1. Note "like to", "hate to", "need to", "have to" and "want to" with a main verb. "She likes to get manicures before the weekend." "Do you hate to wash the car, too? I do." "They don't need to tell her she has to study; she already knows." "We want to go skiing, but we have to do our homework first." 2. I would use the plural: "I like to read interesting books (in general).")
Sometimes I go i´m going to discos. (Note "sometimes" as one word. Use the present tense in terms of something you do habitually; use the present continuous "I am going..." for something you are doing at this moment or something you plan. I would use the plural "go to discos" rather than "go to a disco".)