An article on WorldHum talks about how your appearance will affect your experience while travelling in foreign countries. Particularly a woman asks should she cover up her dreadlocks for a visit to Singapore. There was a time when she would not of been allowed into Singapore with that hairstyle, but times have changed.
Bearing in mind that there are 6 billion realities on this planet and we all look different, the bottom line question is ‘how much effort should we invest in trying to look ‘the same’? Society, whichever one you are in, exerts a pressure to normalize, however bizarre it may seem to the newcomer. People generally feel more comfortable with someone who’s reality they can understand, rather than a person operating in his own unique manner.
The dreadlocks into Singapore question was answered with writer Rolf Potts suggesting she should chop her dreadlocks, as locals in Asia would fixate on them, rather than allowing her to interact freely.
In my experience travelling around the world I would say that a ‘scummy appearance’ is never appreciated and will attract negative interactions. Having hitch hiked in various countries I have had people offer rides, who have told me they never pick up hitch hikers, but did for me because I look ‘clean’ (not a vagrant / drug user, threatening). I think my answer to the hair question would be whatever your style, you want to project something positive. For more conservative countries, that may require cutting back on the tie-dye outfits and dreadlocks and relating to the locals visually in a manner they are more familiar with.
How does that relate to Bali? Tourists have been coming to mass in large numbers since the 1970′s. Locals have adapted to the international array of people who arrive here and probably more accepting of different styles than in most other places in the world. Still, if you visit a temple you should wear the appropriate attire. When visiting a government office, smart plain clothes are a good idea, in fact the Indonesian Embassy in Singapore will not allow you in without long pants.
Restaurants and nightclubs in Bali do not have a dress-code, so no one is going to give you a hard time about the way you look. The hot weather in Bali means you cannot realistically force people to wear long pants and a jacket, so no nobody does.