There is always time for tea!
Knitting pattern to make 2 sizes of tea cosy: standard 3-cup teapot is 14cm high from top of lid to base, approx 46cm circumference at widest part; small 1-cup teapot is 11cm high from top of lid to base, approx 34cm circumference at widest part.
This pattern is suitable for an intermediate knitter (or a novice who wants to learn how to increase following the instructions, and work the picot ridges). Choose a washable yarn, particularly if you opt for a pale colour, as tea cosies generally get dribbles of tea on them. Acrylic blends are suitable as they also have a bit of stretch to the finished fabric; cotton yarns will look nice but wont stretch.
The last picot tuck in the body of the cosy is slightly deeper than the previous 3, to hide the cast off edge.