can someone explain the best way to repoint bricks without making lots of mess!?

Answer 1

Tuckpointing is a messy job. Your best bet would be to contain the mess with plastic or drop cloths.
First, dig out the old mortor with a narrow mortor pick, small chisel or, in extreme cases, a small grinder.
Then you push new mortor in the space with a mortor palet and a tuckpointing tool. Purchase these at your local hardware store. Good luck!

Answer 2

If you don't have a lot of them to do, they do sell brick mortar in caulking tubes. I would not recommend that for a large job however.