Many people find it difficult to clear their mind of distractions, especially when they are new to the practice. The past way to get past this is to continue your practice. As you do, you will become better at quieting your mind. The other thing you can do is accept your thoughts when they come, which will also help you let them pass through you more easily. As you do, you will be better able to seek God's presence within you and be open to His grace.