First of all, it will make things easier if you've seen the same videos I've seen. They're at slo_bro's video site:
We Want Katamari Videos! Most are by Silent Thunder, but MAS 8 is by slo_bro and MTM is by SnapDragon.
I sometimes find myself unable to do the things I see in the videos, so I have to find ways around that.
MAS 1: This is a good example. I couldn't do Silent Thunder's precise turn at the end nearly as well as he does it. I couldn't go under 0:20 by rolling through the mandarin pieces and ending up at the hard erasers.
For 0:19, I tried to hit 10cm at the mandarin pieces. This required getting all the lipsticks. I got to 0:19 much sooner than I thought I would, but I quickly realized it would be tough to go faster with that route.
For 0:18, I got a few cookies and dashed for the eye drops straight ahead rather than the ones along the wall. With far fewer eye drops, this method required that I get more strawberries and cherries than before. I also hope to land on the compass on my way to the lipsticks.
I realize that getting all the lipsticks probably takes the same amount of time as getting the hard erasers, but it's all about finding a route that works for you.