I've been using Dawn dish soap mixed with warm water and use a soft toothbrush to get the grooves clean.

I clean my clubs after each shot with a Titleist microfiber towel. If the grooves still have some dirt I spit on the face, clean with a bristle brush and wipe again. Never have to clean them after the round since I clean as I go.

Quote Titleist on care of clubs:

"Cleaning and Care for Titleist Golf Clubs
Titleist drivers, woods, hybrids, irons and wedges can be cleaned with mild soap and water and then dried with a soft cotton cloth. We recommend your golf clubs and headcover be completely dry before storage. Storing golf clubs in wet headcovers can lead to rust and corrosion and may not be covered by the warranty."

*** This info can be found at the bottom of this site under CUSTOMER SERVICE - Warranty, Care and Repair.

I use Dawn Platinum Powerwash Dish Spray for removing the stubborn tee paint marks from the faces and soles my driver and woods. I spray, let it sit for about a minute. I have a nylon brush that I use for the irons that alone wouldn't do much on the tee marks on the woods. This spray is so effective I can use a terry cloth to wipe and the marks are gone.

Magic Eraser works best for me and getting those stubborn tee marks off the bottom of the driver. For my irons I use a small amount of dish soap in a spray bottle and a soft bristle brush. Cleaning with some spit and the towel after each approach shot works too :)

i use Simple Green Golf Club Cleaner for my all my clubs including the TSR ball and tee marks. Works really well. I sometimes use Magic Eraser for tougher stains.