Taking a taxi in Thailand is easier when you know simple directions in Thai.

Useful phrase:
ไปที่นี่ค่ะ/ครับ
Bpai tee nee ka/krub
“Please go here.”

You can show your phone map and say:
ตามแผนที่นี้ค่ะ/ครับ
Dtaam phaen-tee nee ka/krub
“Please follow this map.”

If you want to ask the price, say:
เท่าไหร่คะ/ครับ
Tao rai ka/krub
“How much is it?”

These phrases are very useful for travelers and expats in Thailand.