As writers we usually work out of our homes. This is a mixed blessing. On one hand there’s no commuting, there are tax benefits, greater flexibility in work hours, flexibility in dress (heck you can even work naked if you wish) and a home office is cheaper than renting. On the other hand there can be numerous distractions, like children and pets, friends and neighbors who may not see your working at home as work and it is isolated from others. Basically you need space, some office furniture, equipment and good lighting.
Where you place your home office depends on your needs, the available space, the needs of others in your household and how much money you can spare. If you live with a spouse/partner and have children you’re going to have to consult with them and have to compromise.
Start with knowing your needs. How much space do your require? Do you need lots of storage space? Will you be meeting with clients? How easily distracted are you? How much energy do you require? Do you require a permit for a home office? Do you require more than just a chair, desk and computer? Will desk drawers do or do you need bookshelves and filing cabinets? Do you needs lots of peace and quiet and no clutter or can you ignore a noisy environment with lots of clutter and other distractions?
Once you’ve assessed your needs you can then review the available space. For example you might live with a spouse/partner and two children in a single story house. In this case maybe you’ll have to settle on an underused corner of a room. You might wish to consider putting up a screen, which has two uses: one to keep out distractions and to hide your space when company comes. Another option is to store your things in a closet and take them when you’re working. Desktop computer might be on a small rolling desk.
I would strongly advise against using a corner of your bedroom for workspace. I did when I started out and I came to deeply regret it. As I was stuck in the room for sleeping and working that it made both very hard to do.
On the other hand you may live in a large house or condo or apartment or live alone in which case there might be an underutilized room you could convert to an office. If this is the case maybe all you need to do is move whatever is currently in the room out and put your desk, chair, computer and anything else you need in. Maybe some extra lighting is needed or maybe you need to build in some bookshelves. Maybe you have an unfinished attic or basement that could be fixed up for an office.
Finally you may be one of the lucky ones who have the money and space to convert a garage into an office, build a room onto your house or build an outbuilding specifically for writing. In this case you get to start from scratch.
In my case I’ve taken a basement bedroom and converted it into an office. I have some built in bookshelves, cupboard, some filing cabinets, a closet and a desk and chair, with a computer and printer. I have a ceiling light, a small window and a task light. During the summer time, since I don’t have central air conditioning, my office is one of the coolest in the house. It’s not ideal and some day I’d like to move my office upstairs to what used to be a den, but is now used as a library.