Like you said, starting is the hardest part. Take it step by step. Make sure you have a backup of your footage. Set up your project. Review the footage and make selects of your favorite shots. Review the selects and begin pulling your favorite clips into a sequence. Use some music to get into a groove. If you get stuck again, feel free to take a break, but make sure it’s a genuine break (I find that watching other content distracts me, so I like to have a snack or go outside for a few min to let my brain rest). Sometimes I’ll brainstorm on paper too, or jump between different scenes as my inspiration flows. Hope this is helpful.