Unless the air is very warm, you shouldn't let your Peke run around to dry himself over the course of a few hours because he might catch a cold.
Also, you should not towel dry Pekingeses, since this can easily cause the fur to tangle and break.
Instead, you want to just pat him with a dry towel to soak up most of the surface moisture, and then finish him off with an air dryer.
When airdrying, don't swing the dryer back and forth rapidly as this can really tangle up the fur -- unless of course you've given him a puppy cut.
The best way to dry a Pekingese is to go slowly, keeping the dryer at a distance from the body, while using a brush to gently separate and straighten the fur.
It is not a task to be finished in the matter of a minute, so do not rush through it!
A few minutes doing this properly will avoid unnecessary tangling of fur, which later can become problematic mats.
If you're using a regular blowdryer, that is fine, but be careful not to hold it too close to the body or else the heat can quickly burn the skin and coat.
Also keep in mind that your Peke will get very warm under the hot air, so give him periodic moments to cool down.