The map above shows U.S. congressional districts as they are today.
The map below shows U.S. congressional districts as they might be using a computer-generated algorithm to make the districts compact.
There are other criteria that could be added, which is maximum feasible respect for existing county and city boundaries.
Any neutral drawing of boundaries will give some advantage to Republicans and to us white people, because Republicans and whites are more spread out while Democrats and minority groups tend to be concentrated in cities.
That means that in a particular state, Democrats could have a majority of the whole state’s vote, but Republicans have a majority in more congressional districts than Democrats do.
I don’t see any good answer to this. A neutral formula such as the one above would be less one-sided than what we have now.
Once you start to deviate from a neutral formula, you have the present situation, which are districts intentionally drawn to elect or exclude certain individuals or to benefit a certain political party.
List of United States congressional districts on Wikipedia. Detailed maps of congressional districts in each state.