Specially for ppl who don't ( or don't have time to) research or read up a lot.

- First things first, try and re-plan your journey to reach Windermere by 9.15 am. If you can, then go ahead and book a tour with mountain goats and you will be sorted.
- If you are more of the "I will drive around myself" types,  rent a car . There's not much traffic here, parking might be a bit expensive, but advantage is that you can then make the most of your Sunday morning too. Keep in mind, roads are narrow, at certain places there are ghats / winding hairpin bends. Another tip, if you have your train towards the latter half of Sunday, then ensure that you book your car starting Saturday to Sunday. Entreprise rent a car is just near the train station in Kendal, but they open at 10 am on Sunday. That means in summer months half ur day is gone. So rent one as soon as you get in Kendal and return it by Sunday at  15:00. Moreover a car allows you to go to places where the bus won't - like the Hardknot pass etc.
- If that doesn't work for you either, get in Windermere before 13:15 and you will get a half a day tour of the central and a bit of other lakes. Plus you don't really have to worry about missing out on the main toursity spots. With the remaining half of Sunday, you can either roam around Kendal, the Kendal castle ruins are good, and a walk around the city is pretty decent. The wooden trails of Kendal are good too.
-  Bus pass - stage coach offers a day rider with a 11.30 pound pass. Get on the 555 to Keswick, and catch a bus to Buttermere keswick.  Roam around for a bit and catch the bus back to Keswick . Get down on the way near Ashness bridge, click a few photos,  walk or get the next  bus to Keswick and go to castlehead ..it's a short hike, gives awesome views of Derwentwater and that should get you sorted.
-  Now if you still have enough time available (basically if you are done by around 16:00 (it's pretty ambitious I know.... still), I suggest catching  a bus to  Ullswater
-  a quick hike to Halin Fell or aria force should give you good views of the lake plus cover some of the best attractions around. Another option would be to catch a steamer on the lake and enjoy a cruise. Keep in mind that during summers the last bus from Ullswater to Windermere or Kendal leaves at 18:25
-  catch that bus and head to Bowness on Windermere.(You can change your bus to an open top one at Grassmere to soak in the last few hours of daylight).Enjoy the ride, chill off and feast on a dinner by the lake side or take a sunset cruise on the lake.   The last bus to Kendal from Bowness goes at 22.30 in the summer months. (Be sure to check the time table on the stagecoach app)
-  Sunday morning can be planned as per your wish....a lazy morning spent in Kendal, or a hike around Ambleside.
-  if it's the latter, get up early, catch the first bus to Grassmere (around 7.30am) . You can choose to go up till Castle lane near Keswick and view the Castle rigg stone circle and head back towards Grassmere  or get down at Grassmere and start walking towards Ambleside
There are multiple options  for the walk. Stick to the motorway in case you want to hitch a ride if you feel tired,  or try the other routes via  Rydal caves  and keep  following the river Rothay towards Ambleside. The route that goes under Loughrigg is a gentle peaceful walk with  some nice views and bridges.  
-  at ambleside catch a bus head back to Kendal, have a lazy Sunday brunch at Michelle's coffee shop  and head over to the Kendal fort. Its a short hike and gives you nice views of the town. If you are still in a mood to hike, then the Serpentine woods isnt a bad option either. Head back , pick your bags, and catch the pick up service to Oxenholme station, near the Kendal train station.
-  for those who hate to spend time waiting at the train station(Oxenholme), there's another short hike nearby - the Helm which gives beautiful views of the countryside including kendal. It's a short 15-20 min walk to the top and if you have more time on your hands you can keep walking on the ridge.

There you go, a one day tour of the lake district with maximum items squeezed in it.
You will have missed the Eskdale and Ravenglass side of things...but then you can only do so much. :)

This blog has been written based on the author's own mistakes and the things he missed by not planning  in advance. (He did manage to do the castlehead hike( Keswick) , the  Grassmere - Ambleside walk, dinner at Bowness, the Serpentine woods in Kendal, the Howe fort(Kendal again, please skip this..there's nothing here) , breakfast at Michelle's coffee shop, the Kendal fort and the Helm hike.). He wishes he had  done this research earlier or someone had written this piece earlier in order to make the most of this day in Lake district.!!!