# Invoke a guide at the start of a contact in Amazon Connect
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After you've created your flows, you can dynamically determine which guides to show to users. To do this: 

1. Add a [Flow block in Amazon Connect: Set event flow](set-event-flow.md) block to your flow.

1. In the **Set event flow** block, configure a **DefaultFlowForAgentUI** event hook

Guides start as soon as the contact is offered to the agent. They don't wait for the contact to be accepted.

For example, by checking the IVR responses, queue name, and customer info, you can create branching logic in flows that determines which flow ID to set. Use the **Check attribute** block to set your conditional logic and the **Set event flow** block to set the flow you want to send to your agent.

The following image shows the **Properties** page for the **Set event flow** block. The event hook is set to **Default flow for Agent UI**.

![\[The Set event flow block, the Default flow for Agent UI event hook.\]](http://docs.aws.amazon.com/connect/latest/adminguide/images/example-flow-id-sq.png)