Vary the type and scale of patterns used
Personally I would not have this many pillows in a row but the patterns really work well together. Start with a large scale print in the colour scheme you want (floral above) and choose the others based on this. Note how the linear geometrics vary in colour and size - always a good formula. The circular raised flowers in yellow play well with the larger floral and pick up on the colour of the larger geometric.
Keep the patterns in a tight colour scheme - complementary is easy
Caitlin Wilson via Houzz
This is a more adventurous use of pattern when you consider the wall and the ottoman. Similar to the last arrangement, this one uses a large scale print as a departure point for the colour scheme. A smaller and larger linear geometric is chosen in complementary colours. If you want to have a lot of energy add pattern to the wall in yet another pattern. It's too much for me, but I'm pretty plain in my tastes!
Break up pattern with a solid
This is a pretty intense pattern but it is played down by using white and a solid colour in pillows. If the chest was painted white the pattern would be further controlled.
Play down colour, go neutral