In the early game lane phase, you’ll want to grab a ward the first time you fall back to your base. If you have over 80 gold, item space and no ward, then you’re doing it wrong. Don’t feel like you always have to use the ward right away. When you see an opportune moment where you think it will help, drop it. I prefer dropping a ward in the river bush because that’s where most attempted ganks will come from. They’re not going to come from behind you with that tower in the way. If they come at you head on, you’ll have plenty of time to determine whether or not to engage or drop back to the safety of your tower.
Usually, you can go a few levels without worrying too much about wards. But you’ll want to start placing some after level 3. If you know the other team has a jungler, then you’ll want to get one early as possible. Some champions start ganking as early as level 2 or 3 (Such as Master Yi).
Place the ward within the bush. The closer to the middle lane you place it, the earlier a warning you’ll get when opposing team champions are coming towards you. If you place the ward outside of the bush, the vision granted by the ward will not extend into the bush itself. So place them carefully!