2. Why don't you…? It's a bit more of a weak way to give advice.

3. Have you thought about…? It's like you're sharing your opinion, but you're kind of making it sound like maybe it was the listener's idea, or maybe the listener has thought of this thing before, so this is also a fairly soft way to give advice.

4. I don't know if… is a good idea. This is kind of a negative way to give advice or to share your opinion

5. Maybe you should try… The next one is a suggestion to try something, so this is a soft but kind of encouraging expression.

6. I wouldn’t…

7. if I were you, I would…

8. Have you tried…? This is very similar to “have you thought about…” So, again, it's a question for the listener and it's a suggestion for the listener, kind of soft advice.

9. My advice is to... This one is a very clear advice statement because there's some action you recommend for the listener.

10. You ought to... The next expression is "you ought to..." So "ought to" means "should," but "ought to," it sounds more formal, more polite, it's not used as commonly as others, but actually we use the contracted form "oughta." So "ought to," just like "want to," can be contracted to "oughta.