Hey,
So I'm a student in Germany, and since I'm currently a broke one I've decided to bike everywhere while the weather still allows it . I bike for an average of 3 to 4 hours EVERYday (1.5 to 2 hours to work and the same back home) and almost half the distance I cover is very steep (mainly upwards but also downwards) my questions are, besides the essentials (helmet and water) are there things I should watch out for? Like, my saddle is set pretty low on my bike should I raise it? should it be tilted and should I have a certain posture (leaning or upright)??? Any other advice would be MUCH appreciated

Thank you all

p.s Incase you were wondering, I try to keep my pace as fast as I can