To completely stop checking their social media, it may be best to stop following them altogether.
This way, you will not keep receiving notifications of what they are doing on social media.
You should also proceed to stop following people that may be connected to them, as long as these people aren’t close friends of yours.
This way, you aren’t sucked into something that they have posted in their social media that may involve this person that you are trying to move on from.
This can be a temporary move.
At some point in the future, you may choose to start following these people again if you feel like you have moved on from this person emotionally.
However, for now, the idea is to remove any form of temptation that could make you feel compelled to check up on this person that you are trying to move on from.