Tips on becoming a better adc

Find a support to queue with, because lack of consistency from your support is the most cancerous part of being adc.

Pretty sure you can find tons of videos on youtube if you just look it up. The biggest thing an ADC has to consider is walking the line between getting killed and dealing as much damage as possible through constantly attacking. This means you need to know the skills of all champs including your teammates, understand the CDs and how things will play out by being a certain distance away. This is what people refer to as proper positioning.