Taking people fly fishing at a professional level has many different aspects. The biggest, and most important ,would involve safety and generally looking after the well being of a client. Being on the water, especially in a boat, is a responsibility not to be taken lightly.
As a flight attendant explains the safety protocol before a flight, a guide can and should go over basic rules that can put everyone in the boat at ease and allow for a enjoyable float that will take away the anxiety and, allow for the client to concentrate on fishing once the 'rules' have been explained.
Once 'underway', the responsibility of a guide,generally, is to put a client on fish. This is on a sliding scale of sorts. The outcome being based on the individuals level and ability to cast and identify the areas in a river that hold fish.
Surprisingly, as elemental as this issue is for seasoned fly fisherman or even a spin fisherman that has spent time on a river fishing for bass, it is interesting to discover how little the beginner or novice knows about where to place a fly, though they may have fished for years. In other words, where the fish are expected to be on a given day, based somewhat on the time of year.
To be fair, there is a lot going on for the beginner, including the usual inhibitions about not looking completely inept at something that they may have wanted to try for a long time, coupled with the fact they are in a boat with an "expert" and they (everyone) wants to do well and catch fish.
To help perspective clients know what to expect when hiring a guide whether in a boat or wade fishing, here is a list, or a primer if you will, to help the first time paying angler what to expect and what may be expected of them.

First Trip: Top 10 Tips to Hiring a Fly Fishing Guide

Have a personal conversation with the guide about what you need to bring along.
Be honest about the level you feel you are at with casting a fly rod AND casting big flies.
If on a full day trip, ask about food: beverage, snacks and light meal such as a sandwich.
When on the water, don't be afraid to ask questions about the flies you are supplied with or the type of rod you are using. Guides love to give information that strokes their ego and makes them feel as though you actually care about fly fishing and want to learn.
Pay attention to instructions given to you. Accept positive criticism as a way of becoming a better fly fisherman and a way to cut corners on the inevitable learning curve.
Pay close attention to where you are told to cast to. You are looking for cover that holds fish. Dark water....structure, usually in the form of wood in the water. Fish don't hold everywhere in a stream. (Ask questions about this) This will help you understand on your own, where to cast and cuts down on comments from the guide that can lead to frustration for both you and the guide, and will allow for more quiet and enjoyment.
Don't be intimidated by the guide. If you are not comfortable casting while the drift boat is on the move, ask if it is possible to stop and anchor or stop and wade. This can ultimately affect the amount of water you will cover actually fishing,however, it may be more practical to fish fewer spots more effectively.
Take the time to observe the river and it's surroundings. We encourage clients to ask about plants, trees and birds and we feel good about sharing our knowledge to give a client a well rounded river experience that goes beyond putting fish in the net. Not all guides take the time to discuss other aspects of a river beyond the fish themselves.
Take the time to consider the guides role in your trip down a river,and the responsibility we assume to try to ensure you have a safe and above all,fun time that you cannot wait to do again.
Have fun! Cannot emphasize this point enough. You are paying for information and fun. Don't take the catching of fish too serious and capitalize on the fun part, and if all goes well......you will have come away with an experience that puts a smile on your face all the way home and beyond!

Mark Karaba
The Fly Factor