There are many ways to get around in Hua Hin, Songthaew runs the same routes all day and cost not so high starting from 10 Thai baht, and price depends to the distance you are going to. If well out of town, you pay more. There are numerous motorcycle taxis and tuk-tuks, fewer car taxis. Negotiate price beforehand, but you will not get a tuk tuk for less than B100 over any distance (unless you are lucky) if you are a Western tourist. There are quite a lot of upscale tourists in Hua Hin and prices are sometimes adjusted upwards. Better to clarify the matter ahead of time. Motorcycle rentals are readily available. Hua Hin is very flat, and bicycle is a good way to get around locally. Rentals available, but not so prevalent as motorcycles.
You can use the local songteows, and a white one leaves from the train station and travels south along the main road to the Huaymongkol Temple, which is some distance from the city B40. It then goes to the floating market (B20), and then back to town(B20)