make sure you can make trades work in your favor. If you ever notice if your adc playing ham you need to go ham too stick Next to him. if you ever notice whenever a trade goes horribly its normally because the adc will go in for a trade then lose it by taking 2 aa's/ 2 spells from both the enemy adc and support while only trading his one aa/spell onto one person. in order to prevent these bad trades and force bad trades onto the enemy duo try to position yourself close to the adc to be able to trade whenever he wants. another thing is that try to let the adcs decide when to trade because often time if you go into a trade thinking they have your back but they dont because they have 3 low minion in front of them or a q on cd. As an adc main in Gold V this is something a lot of supports lack. I am a support/adc main so i know most of both sides to the coin while leaning on the adc side.
Lastly if an adc pings to not go in dont go in. this is a univeral rule for always and forever in league. If you ping someone to go ham on them and your friend pings danger dont go in. if one person wasnt expecting to go in and all of a sudden you come in they are not prepared and more than likely wont react/ make a mistake somehow when trying to dive someone as exmaple. Its better to cut your losses then give up bounty gold/ double kill under a tower.