I’m not an expert in Scrum methodology, but after working and collaborating for 3 years as part of a Scrum team, here are some ways we’ve a got to introduce User Experience practices into agile development:

• Getting User Stories talk about real people and needs (Personas)
• Getting Epics talk about user scenarios
• Product backlog grooming on Design Studio’s sessions
• One sprint ahead for High-fidelity designs (better option maybe would be a Design spike)
• Usability expert consultancy during the sprint
• Cognitive walkthrough during review sessions