If you are overcalling and you have two long suits, at least 5-5, you can use a handy bit of system to show both suits at once and let partner choose between them.

We do this using one of two artificial bids: A jump to 2NT (not 2NT over a two level bid because that’s not a jump) shows the two lowest unbid suits – easy to remember because it’s the two Not Top suits.  This is called the unusual 2NT. A bid of opener’s suit shows two other specific suits, as outlined in the panel above.  This system is called Michaels cue bids.

The panel below shows what your partner should do when you make one of these two types of bid.