How does personal Confession work from a Reformed Perspective?

My question is pastoral in nature; I apologize if it seems naive. I am leaving Catholicism and transitioning to the Reformed Church's perspective, but there are still things I do not fully understand. I understand that confession can be communal during the worship service. But I also understand that there is space for personal confession. What happens when I sin and want to ask God for forgiveness? Is contrition and a sincere confession enough? What are the elements that constitute a good personal confession before the Lord? Thanks in advance.