The simpler you speak, the better. No need to use long complicated phrases such as “Do you know how I can get to Jatujak market?” Instead: “Jatujak?”

There’s the common wisdom that in India and Phillipines everyone speaks English. Perfectly. It’s not true: it’s not perfect, it’s pretty far from being perfect, they won’t understand idioms and slang. Add to this their accent. It’s actually basic English. And moreover, not everyone speaks it. I had a girlfriend from the Phillipines who wasn’t aware that the word “were” existed, neither was she able to pronounce it.

Using japanese-style grammar in English can help also. Instead of “I’m going to the airport, where can I find a bus?” — “The airport, bus, where?”. Without ですか ending your question, though :)