If you have no idea at all what you want to do, there are many ideas abound online or in books and magazines, that can help you decide which way you want to go. It can be a gym if you do not have time to go to the fitness club, a playroom where your kids can entertain their friends; a home office, a bedroom, or an arts room.
Alternatively, it can be a combination of ideas like an entertainment center where you want to include a bar, a home theater system, and possibly a pool table or table tennis where you can invite your friends for a party; or a workshop, laundry, and storage area in one. Of 
course, we all need to install a bathroom in the basement especially now that this is going to be a functional space.
The possibilities really are endless.
Effective Planning
However, before you can start your project, you will need to ensure that you identify the purpose of your basement, and stick to it, as this is the main foundation of your project. The requirements vary on each of these ideas, so you will need to stick to a decision. When you have decided, then you can start planning.
As with every project, we all need to plan. Having decided on the purpose, you have to now sit down and lay on the drawing board how you intend to make a success of this project.
Make an accurate measurement of the entire basement and on a piece of paper, you make a rough drawing of what you have in mind, making considerations of all the rooms you will need, doors and windows.
You must remember to include in your map what people tend to forget usually – the locations of your furnace, sewage pipes, and sump pump and water pipes. It is essential that you will have to provide easy access to these utility areas as occasionally you will need to deal with them.
A bathroom or a laundry room will need to be positioned beside the water heater so that you may avoid any additional extensive plumbing.
Everything that needs doing – from carpentry, electrical wiring, plumbing, insulation, drywall installation, painting – must be listed down. You decide which ones you can do yourself and ones for which you can hire a professional contractor.
We all know that the cost would go down substantially when we do things ourselves. However, there are things that we can leave to a professional. Nevertheless, do get three bids for the expensive stuff, so that you can compare and go with the lowest bidder.
Most contractors on the average charge from $15 to $25 per square foot. Not cheap therefore you must ensure that whatever you take on are things that you are up to doing. You do not want to double your cost by hiring someone else to perform a repair later on for something that was not done properly.
You must check your local building regulations and obtain the necessary permits as required. Read more
Budget
Overall, you need to put the estimated cost for each item you have listed. There are sources online that can help you make rough estimates of cost of materials and labor.
Most times, we forget to list down many things especially under the materials list. Therefore, to make a rough estimate of your materials cost, multiply the amount of what you have come up so far to 3 times as much to give you an allowance for the things that you may have forgotten.
Again, log a contractor’s estimated cost at $20 per square foot, using the midpoint of the average range as mentioned above.
Summary
Finishing a basement may be a hug project but it will be cost effective in the end. The important thing is that the more time and effort you put into your planning, the closer you can get to a more accurate pricing. With better planning, you will be more ensured of great and long-lasting satisfaction.