Many beautiful hikes start from Les Diablerets, or the Col du Pillon, where you can also take the cable car to the Glacier 3000.
Here is a suggested hike: https://swisstopo.app/i/5/A2WRR8R2 (the link will allow you to download the Swisstopo app which provides high quality maps of Switzerland for free). This hike is 5.5 hours long in total but can be shortened by taking the bus to or from the Col du Pillon.
Alternative: 20 minute walk to nice picnic spot: https://swisstopo.app/i/5/9NAE3HVC
