At first, you need to identify and understand the infrastructure of the building and also determine whether it is a home or a commercial building. Without knowing these things it will become very difficult for you to find a general contractor.
Now, you should try to get as much information as possible about different contractors. You can ask your co-workers or friends to help you in this regard.
Then select two or three most experienced general contractors having a rich history or a proven track record. Try to know their complete background which is essential in making the right choice.
Discuss the details of your project with these contractors individually and get an idea of what they can do for you and how much time it will take them to complete the building.
Now try to get estimate of cost from each of them. Do not disclose how much money you want to spend on this project. Just get information about their estimation.
Try to evaluate the quality of material they will use which will help you to select a potential general contractor which is more suitable for you.
Select one from these two or three contractors who is suitable from all aspects including cost, time and the quality of materials he will use in the construction of building.