To focus on the sustainability element in an event's promotions, event organisers should be considering ways to promote their event through less paper-intensive measures including online promotions, multiple-users posters & flyers, reducing the size of disposable flyers and ensuring materials consumed are sustainable (e.g. recycled paper and environmentally friendly ink).
In addition, one of the major benefits of making your event more sustainable is the benefit of promoting these sustainable practices implemented at your event. This could be done to attract more people to attend your event, attract more sponsorship deals, attract higher quality speakers and get more media coverage for your event. An easy and cost-effective way to do this is to get accredited for sustainable practices at your event and place them on promotional materials. This may even lead event attendees and staff to take up more sustainable practices in their lives.