Here's my routine: do a few wraparounds and reversals for extra early points. Then get as many "nice entries" as possible, by going to horizontal speed. Vertical height is bad early on, it means you won't get the speed bonus from "nice entries". With around a minute to go (more time left when you get better) or around 17 nice entries, tailslide out of water, starslide up to jupiter or saturn, then drop back down. Then tail/starslide up to new horizons, then back down. Then your last jump is to the restaurant.
Remember while in the air, do as many frontside and backside rewinds while corkscrewing as possible, as these boost your multiplier really well. Your base score-don't worry, reaching the plants boosts that up.
Good luck! If you don't know any of the trick terms used, you can find them with a google or youtube search.
240.3 million, personal best =)
Here's my advice to beginners. Go on youtube and watch the tutorials on tailsliding and starsliding. Remember, to get good air out of the tail and star slides, you have to approach the water as close to parallel to the surface as possible.