Insert a new layer.
Start by drawing a big heart in a new layer - set it to fill only.
Then draw a circle over the top. Make sure it lines up nicely on the edges so it looks like one continuous smooth shape.
Take the Rectangle Select tool and draw over the bottom of the heart.
Then Delete.
Rename the layer 'balloon'.
Duplicate the balloon layer. Set it to Color 2 - go to Adjustments > Hue/Saturation and change the color.
Then click on the canvas with the blue arrow tool and push in the sides.
Duplicate the balloon (Color 1) and move it to the top. Then squish it.
Do the same thing but now for Color 2: duplicate, move to the top and squish.
Repeat 2 more times until you have 3 balloons of each color.
In a new layer, draw a Rounded Rectangle to cover up the bottom of the balloon.
Draw a different rounded rectangle in a new layer for the basket.
In a separate line, draw 6 thin lines to connect the balloon to the basket.
Move the lines layer under the basket layer.
Fill the Background layer with a blue gradient.
In a new layer, draw a white cloud using the Cloud Callout shape, moving it so the other bubbles are off the canvas.
Draw another one in a different layer and move that one behind the balloon.
Add the following effects by going to Effects > Photo > ...