Assuming you would like tips on how to stay in formation while walking:
When walking in lines, it is important to keep your head up and look straight ahead. You should also try to keep your shoulders squared and your body relaxed. It is also helpful to slightly exaggerate the movements of your arms and legs so that everyone in the line can see what you are doing and follow along easily. Lastly, be sure to walk in step with the person next to you so that the line stays even and cohesive.