Clustering based on features of varied importance
If education level and income are more important than other features, you can multiply those features by a factor (greater than 1). That will allow the  clustering algo to focus more on those features than the rest.
For larger datasets, with features where the differences are not so obvious, you will need to rely on your judgement based on the end objective of the clustering. If you have a target variable in mind, you want to choose or boost those features that are highly correlated with the target