A few tips to help get you started! Don't build a sloping pond- it should drop straight down if possible. This will help keep predators out. If straight down, you may need to support/reinforce the sides. A ledge atleast a foot deep is great for plants.
Have plans in place for the dirt (what are you going to do with it, where will it go etc). It will be a lot more dirt than you can imagine (and it's not going anywhere once it's rained on).
Also have plans in place for outdoor electric service. If doing it yourself, this involves permits and L&I.
Make sure you know where your water service will be and how you will be doing wcs and filter cleaning before starting anything. Things such as ground drainage around the pond or overflows on the pond or bottom drains in the pond are things worth mentioning.
Do some planning before you start to make things easier in the long run.