1.) After completing Level 1:1 "Revolving River" go back to the HUB Area "Forest Plaza" and buy the "Double Jump Spin Attack" in the Armory!!!
2.) Pay Retro the little money he is asking for ;)
3.) After completing the first Boss "Furious Frog" it is VERY likely that you have already gathered enough Magic Seeds (4) to proceed to the Summer levels of the map. So, after returning the Magic Bark to the Season Tree and being rewarded the green arrows, simply talk to = activate the little Treeling in "Forest Plaza" left to the Magic Shop to proceed.
4.) Experiment with and stack up on Magic Attack Potions...
5.) Try and find Mana Ore to upgrade your Bajonett and make new moves become available :D