Make sure that your foundation is level. Nail your floor properly to the foundation blocks. After the floor, make the frame for your walls and then for the roof. Make provisions for your windows. Pre-fabricated kits can make the job easier, but it can much more costly. There are many books and websites which can help you do your plans, there are even ready made plans which you can just customize to achieve the desired size. Yes there are ready made sheds that are available for you, but this can be quite costly and many of them are even overpriced. In this economic time it s just not advisable to pay someone to build a shed for you. A storage or garden shed can be a simple do it yourself project that would require only the minimal carpentry skills plus it can also be source of pride and joy as this is a creation of your own two hands. Depending on your choice as roof material, you can now finish your roof placing your chosen material as per manufacturer s instructions. Safety is always the key, as you would be working on the roof, there is a chance that you may fall off. If possible, get someone to work with you and make sure that when using ladders or other tools for elevation that it is secure. Steel sheds the strongest shed finish, this type of shed finish is used in areas where there are harsh climates. This finish is very durable and rugged and provides maximized security against any invader. This though can be the hardest to work with. Aluminum shed best used in temperate climates, aluminum sheds is more affordable than steel sheds. It seems that even though you have a big home, space is lacking. It s easy to understand why most homeowners would want to have a storage shed. In this economic times, not many of us have the money to either get a builder make a shed for us or get pre-fabricated shed kits to have our own storage sheds. It is important that your door fits like a glove on its frame. Take into account the small space that your hinges will occupy. You don t want a shed door that is not leveled. The top half may either be hitting the frame and there s a gap on the lower half, or vice versa. Not only will you not be able close your door and lock it properly, but you can also cause damage to your door frame.