You will also need something to play your battles on. Any firm, level surface is best, such as a tabletop or an area of floor - most kitchen tables will do. It's a good idea co use an old sheet or blanket to protect the table from scratches.
Some players make a special gaming board from chipboard or other similar material (divided into two or more pieces for ease of storage) which they can use on top of a table to extend the playing area.
Whatever you use, you will find that an area approximately 6' x 4' ls about right for most battles.