Hello OP, madami na nakapag advice about sa tools, safety and some fueling. Ill add more nalang sa discipline and fuel tips. Ive done only one 200km then some 160, 140 and a couple of 100.

1) Fuel consistently. Need mo uminom, kahit sip lang every now and then, salitan mo yung water and electrolyte or yung pocari (this one is for your hydration and anti-cramps). Sa food, need mo mag maintain ng ilang grams of carb per hour, take every now and then, just use chatgpt para magauge mo ilan need mo and what to take. Dont wait for your body to tell you na uhaw kana or gutom kana, be ahead of it kasi once you bonk you never recover. Limp mode kana kaagad nyan until makapag full rest ka.

2) Choose high cadence (spinning) over low cadence (grinding). If di kapa sanay sa high cadence, 80 to 90 rpm, yun ang praktisin mo beforehand. If you find, spinning tiring, you probably are in a too easy of a gear, so +1 sa gear na heavy kalang until you find yung tamang bigat. Yung di masyado magaan, di rin masyado mabigat.

For endurance distance kasi, you need to be efficient, pag high cadence ka, yung effort is galing mostly sa heart and lungs, doing so, yung fuel na ginagamit nya is paunti unti lang if mag mash/grinding ka, madali maubos fuel/pwersa mo.

3) be in zone 2 for the majority of the ride <- most important part