krishnabemtech, If you have no other information, you should probably create 8 indexes (1 on each column). This would cover any query on a Single column and DB2 can get a RID list from multiple indexes and AND/OR them to access the appropriate rows when multiple columns are use in the Where clause.
Another approach is to ask the people who will be querying the table how they do it. Is there a column or set of columns they 'always' use. If you can determine a tendency, you could create a multi-key index (or more than one) to handle the majority of the request and individual indexes on other columns.