The lion is the king of the jungle, or, more accurately, the savannah. Lions live in groups called "prides", with the males (the lions) defending the territory and the females (lionesses) doing the bulk of the hunting. While lions certainly are regal, they are also a bit lazy -- they sleep for twenty hours a day or more! Of course, it is so hot on the African savannah that sleeping all day may be a good idea (especially if you are wearing a full-body fur coat), but it would be completely appropriate for you to draw most of your lions snoozing, because that is indeed what they do most of the time.
We think of lions as being light brown, but many of them are a paler shade of brown, almost a creamy white at their belly that darkens just a little up toward their back and shoulders. Other lions do have the classic golden coloring, and males' manes are especially dark, all the way to a medium brown.
When you are drawing or painting lions, you have a lot of choice in mediums to choose from. Pencil is a fine medium for lions, as is pen and ink, or even watercolor. There have been plenty of huge pieces that used an almost abstraction of a lion's head, either in wildly colorful pastels, or in multimedia like yarn and felt to accentuate the fantastic mane. What you do to create your lions is, of course, entirely up to you.