(a) If you have a friend or acquaintance who belongs to a different ethnic group from you with a distinct language, they may be willing to share their family history with you. It is very important to be polite and not to put any pressure on someone who is reluctant, however. They may have good reason to feel unwilling to share experiences which may have been painful.
If they are willing to talk to you, find out whether they migrated to the country you both now live in, or whether their parents or grandparents did so. If so, when did they arrive, and why did they come? Try to trace the language history of each generation. What languages do their grandparents/parents/brothers and sisters speak in different domains? Does your friend still speak their ethnic language? If so, who to and in what contexts?
(b) People are often unaware of the range of ethnic groups living in their area. How could you find out how many ethnic groups there are in the area where you live?
(c) Walk down the main street of your city, town or village and photograph and/or write down all the material which you think contributes to the linguistic landscape. You should take note of everything visual which has the goal of communication. Note where it occurs, its size and colour, and any other relevant features. What clues distinguish between an "official" sign and an unofficial or informal sign? Who do you think are the intended addressees of the official signs compared to the unofficial signs?