IMO It is helpful to remove the "senior" or "junior" title when working with them.
Work with them. Provide guidance when needed. Learn from them. Trust them. Consider their opinions. Help them provide you with information on things you are not familiar with. Praise their accomplishments in public. Critisize mistakes in private. Provide useful feedback
Have fun :)
Team / Dev Lead does not mean you need to know every bit of code being written rather concentrate on bigger picture. You need to lead by providing guidance and make sure you are not trying to micro-manage people which may be landing you to compete with your team members. All projects have leads but there are developers who are very good in their work, the more you give credit to their work, the more you become trusted and lead status otherwise you will only be competing with your team members.