My quick idea on tips:
1) I use the definite yes or no clues first, such as "The person who arrived at 5:00pm is Maria," or "The frog owner is not Vincent."
Those are my easy ones where I can just click a yes or no.
2) Then the five person clues, again, that's a whole lot of no's that you can get in one fell swoop (9 X's)
3) Then I match everything. So I start from one end/one box and make sure all are crossed both horizontally and vertically. So if I see that the person that arrived at 5 is Maria and that Maria didn't own the dog, then I know the person who arrived at 5 didn't own the dog.
I make sure I fill in as many X's and O's as I can to keep it complete.
4) After that I do the later/earlier clues. Unless specifically stated (arrived the day before/day after), this can be general - could be 4 days before or just one day.
Example: Maria arrived after Vincent.
I take this and say if Maria arrived at 6 pm, Vincent could arrived 5pm, 12 noon, or 7am. BUT Vincent could not have arrived at 6pm (Maria) or 9 pm (that's after Maria, not what the clue stated). I have drawn lines with my fingers going down one box too keep myself from getting confused.
And honestly, a lot will come with practice and repetition. You will start learning a lot of the clue phrases to look for, making it go faster. You will learn little cheats in your mind, and come up with better ideas. As long as you are still having fun, don't worry.
I'll say this - when I started playing here in summer, some of these solve times seemed impossible - heck I couldn't even figure out how some of those puzzles where ever solved and I considered myself good at logic puzzles. But in these past 5 months or whatever, I've learned so many tricks, I've set a few records myself. But I kept doing that because it was fun. It was fun to solve a puzzle that took 20 minutes or I had to start over 4 times. I didn't really worry about solving time or percentage for the first months, because that wasn't where my mind was. I'd stop if I get frustrated and try again later, or move on.
So my real advice is, take your time, read carefully and just have fun. Let it become natural.