You could say, "I hope you'll let me be your exclusive personal tour guide," or "I'd like to sign up as your tour guide." Or you could just ask her for a date while she's in town.
"Do her special guide" is incorrect--I'd write "be her special guide" or "give her a special tour." But "without any other guy in my way" is correct and crystal-clear :)
Are you thinking about/ Are you planning to come and visit my town?
Yes, I'm gonna come there in September.
That's great! I'm looking forward to meeting you.
You aren't engaged any more, are you?
Nope, I'm single now. [Single really means not married rather than not engaged; she'd probably be more likely to say, "We broke up."
I see. So, since you're single, I want to sign up to give you a personal tour. [But---would you not have offered your services as a friendly tour guide if she were still engaged?]
All right. I'll look forward to it. ["it will be my pleasure" is usually said when you are going to be the one providing the service. "Thanks for saying you'll pick me up at the airport next week." "No problem, it will be my pleasure."
[native speaker and writer, not a teacher]