Please speak slowly as I am just now learning Thai. พูดช้าๆได้มั้ยครับ เพราะผมเพิ่งเรียนภาษาไทยครับ :D You may put the word "โปรด or กรุณา" at the beginning of the sentence to make it sound very politely. The above sentence itself is still polite, though. Please note that there are so many ways to say the sentence in Thai.

กรุณา พูด · ช้าๆ ผม เพิ่ง เรียน ภาษาไทย gà-rú-naa pôot · cháa cháa pŏm pêung rian paa-săa tai - กรุณา gà-rú-naa please ; kindly - พูด pôot talk ; say ; speak - ช้าๆ cháa cháa slowly ; unhurriedly ; leisurely - ผม pŏm I (used by men only) - เพิ่ง pêung just ; just now - เรียน rian learn ; study - ภาษาไทย paa-săa tai Thai (language) Copy and paste Thai text from the first line into Google Translate if you want to practise listening.

Informal when talk to friend could say "pood cha cha noi krap phom peng hud reain pasa thai " Vocab Peng :just started to do something Noi krap : same as pls but informal but still polite

Nattaya, Thank you for the reply and also for providing the pronunciation using the English alphabet ... very helpful

Poam peng hud pood pasa thai ka ru na pood cha cha dai mai krub ☺