Fake flower arranging

Hiya.

I have a dry hire venue, so I'm pretty much having to hire everything such as chairs, cutlery, glass, alcohol... this is taking a big bite out of my budget, so i have decided to go DIY with the dressing of the venue. It's a barn, so I wanted a rustic feel.
I've slowly started buying some fake flower stems as and when I see ones I like in the range or garden centres.I'm on the look out for large rustic vases, watering cans and milk churns to fill with the flowers and foliage...My question is to those brides that are planning on, or have arranged your own flower decorations and how they turned out. I keep looking at the stems I have brought so far (currently stored under the bed in the spare room) trying to imagine how I am going to arrange them so it doesn't look a bit naff as I know it is a bit of an art form flower arranging. I am as creative as a blunt pencil.Any suggestions, ideas etc would be most welcome. Were there any particular websites, you tube videos that you creative brides used.Thanks x