OPK Questions

Helen 🦕😄
Hey all. I've been taking OPKs intermittently and I'm going to order some of the strip kinds. A few questions.
1. Is it possible to pee too much on it? 
2. Does it always have a white line under the test window? 
3. Some people say if you're pregnant it shows up. Does it always? 
4. If I'm at work during the best times to test can I just pee on the strips or do I have to dip it?