Caring for antique writing desks starts with keeping the wood clean and polished. So the first step to taking care of an antique writing desk is to get a rag with lemon oil and to begin to gently rub down all the wood.
Rub the lemon oil with the grain. Many restorers like to use old socks so they can feel the contours of the wood. The lemon oil helps to attract dirt and make the natural shine of the wood come out more clearly.
Gently rub down the wood with rags. If you're still not fully satisfied, consider a second coat.
Once the base looks good on the antique writing desk, then look at using some wood polish to add that last little shine. Old English is a good example of a product that some people like to use to help maintain their antique wood desks.
Repeat these steps as necessary, and keep unnecessary food and liquids away and your antique writing desk will remain beautiful and well kept.