for (Contact c:[select id, name, firstname, Individual.id, Individual.FirstName, phone from Contact where id =:theId]) {

        String typeName = 'Contact';
        String fsName = 'FieldSetname';

        Schema.SObjectType targetType = Schema.getGlobalDescribe().get(typeName);
        Schema.DescribeSObjectResult describe = targetType.getDescribe();
        Map<String, Schema.FieldSet> fsMap = describe.fieldSets.getMap();
        Schema.FieldSet fs = fsMap.get(fsName);
        List<Schema.FieldSetMember> fieldSet = fs.getFields();
        List<FieldSetMember> fset = new List<FieldSetMember>();

        for (Schema.FieldSetMember f: fieldSet) {
            String fieldName = f.getFieldPath();
            c.fieldName = 'something';
        }
    }