A friend of mine is playing a stylist Sim and having problems with clients showing up at the salon. Is there a mod and setting that would prompt them to go to the salon? Or is it that they work and aren't available during salon hours? If that's the case, is there a way for the game to prompt sims who are available to go to the salon?

Do you mean that the Salon is not drawing a crowd generally, or specific sims are not showing up as promised for their already agreed upon makeover sessions?

What many of us do is go and find these clients who otherwise aren't showing up. Similar things can happen with architect clients and intended chess and martial arts opponents. Tagger allows us to see map tags for all sims in town or various subsets of them and to see what they are actually doing (or supposed to be doing), or MC can be used to Focus on any sim who is on the map someplace. A MC > Sim > Status > Career report will reveal their working hours. A sim who is pushed out of work or school for such an appointment will probably be pushed back again until their shift or school day is over, so that doesn't always work out well. If they were merely having a stroll or enjoying themselves someplace else, or hibernating in their houses, they should be pushed out of those kinds of activities at least once to show up. If they are...I don't know, giving birth or something with a higher priority like that, they may very well ignore such an appointment and that doesn't seem totally unreasonable.

If there doesn't seem to be a reason why such a sim isn't showing up where they are expected, I would not be above using a MC Sim > Basic > Invite Over command on them to see if that gets them off their sofas (or whatever) and moving towards their expected appointment. Of course, we need to Invite Over to the correct lot, or to our active sim if they are already there, so it makes a difference on whom or where the command is issued.

Thank you. I will definitely share that information so she can track down any errant clients!

Had another thought in connection with the stylist clients not showing up, due to conflicting work hours.

Is there a way to set the Stylist's career hours to be outside of the regular work day?
So instead of working 10-5, maybe from 2 to 9?
Or have a stylist work weekends to capture more clientele when they aren't at work?

Not sure if this is possible but thought it would actually be more realistic.

I have sims in the salon career and they don't all work til 5, as you progress your hours can change. I've had sims work until 7 or is it 8 pm? I have used MC with my design and stylist sims many times and it works more often than not. Once your sim progresses very far they are almost never actually at the Salon. You click accept and the sim should go to them. Sometimes you just have to wait at least 30 sim minutes before they show, but they usually eventually show. If not you can call them home using MC as Igazor suggests...in my experiences all makeovers generally happen at the sims house. Only a few are ever at the Salon. Just remember you have to stay on your sim or they run off to watch TV or some other thing and the client get's mad.

Thank you. I will be sure to let her know that she's actually doing what's best to have the clients come to her.
She's not had much success with the Salon or the regular generated jobs as the clients cancel or just aren't available.
But using testing cheats and spawning jobs has been working well.

I will definitely be keeping these tips in mind if one of my heir household Sims wants to become a Stylist.
So much easier to max this career than get 100 great reviews for my current Architect!