I can't give an answer from experience with an Afro, but although I have had many, many ticks over the years, I haven't had any on my scalp, that I know of. I am very sensitive to the itching of a tick when it burrows in -- that is how I find my ticks -- so I am pretty confident that I haven't had any on my scalp.
To what do I attribute a tick-free scalp? I cover my hair completely with a scarf or a small towel -- sort of like a turban -- when I am working in the garden or my woods. I might find several itching spots a day after a long session working outdoors, and -- voila -- ticks! But over many years, none have been on the scalp. So, my answer is that prevention is most of the battle. You might also consider spraying your turban-like covering with permethrin. @Ian Campbell says permethrin is preferable to DEET for ticks. See his comment, below.)
As for what to do if your scalp develops an itch, I have found that it is easy to feel the tick with my fingertip even if I can't see it. So you might be able to localize the tick by touch and then guide a friend with tweezers to the tick. No matter what kind of hair you have, you will need help.
If you don't feel the itch -- not everybody does -- I don't know what to say.
PS I live in an area -- Northern Virginia -- with lots of ticks.