Add bright accessories
If your garden is sunny and you want some shade build a simple structure and put some wicker or willow on the top to keep out the midday sun, as an alternative you could grow plants such as vines over it.
I also loved the bright turquoise boat, now it is unlikely that you will be able to have this in your garden but you could add a splash of colour with your accessories, for example you could use an oilcloth tablecloth in bright colours.
Now all that is left to do is light the barbecue, open the wine and relax.