It’s not possible to make your account entirely private. The following will always be publicly available to anyone that visits your profile:

• Your profile artwork, description, and website links
• Your likes
• Your re-posts
• Comments you've made
• Who you follow
• Who follows you

However, you do have the option to make all of your uploads and playlists private. This means that no one will be able to listen to your tracks without your explicit permission. You can read more about changing your track or playlist privacy settings here.