My recently completed Imperial Fists tactical squad. I really wanted to get a good strong yellow for these guys. I know that these days people tend to go for a murkier battle worn look, but I always loved the old 2nd edition canary yellow colour, so I was determined to make them so bright you had to wear sunglasses to look directly at them!
The trick to getting a strong smooth yellow wasn't as hard as I thought it would be - simply undercoat with white spray and then apply about 3 coats of your chosen yellow. I thinned mine with about a third medium to avoid any of the clagginess that you can get with citadel's lighter colours. The only problem is that you then have to painstakingly black in all of the other details on the model, but the results are worth the effort.
I'm looking forward to finishing off more of the army so I can get some battles in!