Traveling around with English is very easy in Malaysia
High levels of conversational English is widely spoken in major cities and tourist areas in Malaysia. You should be able to get around and get assistance in English with no problem whatsoever
We used to be a British colony so English used to be an official language. It's no longer the case but it's still used in many businesses, media, and public service. In fact I'd say Malaysia is second only to Singapore in all of Asia in terms of English proficiency
In cities like Kuala Lumpur, Penang, Malacca, Langkawi, Ipoh, English signage is everywhere and almost everyone speaks it to varying degree. A portion of upper middle class families even use English as their primary language
In rural areas, though, it will be tougher to get by with only English, but even there you should still be able to communicate albeit with some effort
So bottom line is if you're visiting Malaysia don't worry about not being able to get around with only English!