How to achieve this soft color/light?

I've been taking pictures for about 2 years now, so not very long and my photos have always been very bright and colorful but i want to be able to do soft looks as well.

i love the color and light in this photo:

how can achieve this either with lighting or photoshop? I know some of it HAS to be post production, maybe desaturating colors or something?

Heres one of my pictures, i feel like it woulda looked better if it was soft like the photo on top

and if anyone is curious i shoot with a nikon d60, and i have two 250w soft boxes and two 250w photo flood lamps for fill/background light. I don't have a lot of money for new equipment so if someone could gimme a cheap alternative to making this look possible?

You already hit the nail on the head. The "soft" look is imitating the look of some old films, and is usually achieved in post-production by selectively desaturating, ie adjust the colour curves for each individual colour. You would normally also add a colour cast.

There are other ways too - the link I've added shows one of them. Have fun!