One of my favorite bedding collections is this striped beauty from Dwell Studios
At $250+ it's not in everyone's budget.
Here is a look for less option that can give you the same look/feel while you save your pennies for the Dwell version. :)
You can either add yellow trim to it yourself or get a coverlet/comforter/blanket in a yellow shade to fold up at the bottom of the bed.
The look for less duvet set ranges from $25-$35 and the pop of yellow comforter ranges from $19-$24.