Set the data set type to Daily Summaries, the date range, "Search for" to Countries.
Enter the country name in "Search Term"
When you find your country, click "Add to cart" (even though the info is free!)
The database will take you to a map that outlines your country. You can click "View full details" to find the available weather stations in the country, and add an individual weather station to your cart.
When you check out, make sure to specify the output format: Custom GHCN-daily csv
To process your order, you need to input your email address. You will receive an email when your order is finished processing (usually only a few minutes, unless your dataset is very large).