Use the phrase "Like I said, ___" when you're going to repeat some advice or opinion that you said before. For example:
A: I don't see it.
B: Like I said, it's on the right!
Two times when you would especially use "Like I said" are:
- When you gave someone advice earlier, and now it's clear that you were right.
- When you gave someone advice earlier but they haven't done what you told them to, and you want to repeat it.
You can also use phrases like "Like I've said before" and "Like I always say".