@CloudyMrs in addition to the resources already shared, I would add a few tips.
1. The further north, the less will be open on a Sunday, so plan ahead. The hotel in Tarbert is a welcome exception. You’ll be fine in Stornoway.
2. I recommend not cycling on Skye. The main road east of Portree is the most terrifying road I have ever cycled. When I next go back, I will cross to Ullapool, ride to Garve and take the train back to the start in Oban.
The islands are so beautiful. Have a great time.