This is a simple gate design that's strong, light and fun to build. It should be do-able in an afternoon, but requires a small amount of joinery. If, like me, you're pretty handy, but interested in building your woodworking skills, then this is perfect for you. This would also make a good teaching project!
I usually start with an abstract concept, and develop the design - sketch, think, repeat. Usually, only the core concept lasts all the way through to the final version. This particular design is flexible. You can easily modify the pattern to suit the width and height you will need. I have attached a sketchup file of my gate. Feel free to use this exact file, or modify it to suit your needs.
Since this was a weekend project, I didn't want to spend a lot of time preparing lumber. So, as I developed the design based on pieces of hardwood that I new were available at my local home improvement store. I made allowances in the design to tolerate the probable warping or inconsistent dimensions of their lumber.
Note: spend a good deal of time selecting your lumber. You want to look for straight even grains in hardwood. Also, it helps to look with one eye down the length of the board to detect and warping.
A note on sealing/finishing: Normally, I use a molten mixture of beeswax and mineral oil. However, due to the outdoor exposure of this gate, I'll be using a simple low-voc oil based clear finish. Use whatever you like.
Take your time here, this is the most crucial part of the process. Since we will be relying on the precise alignment of the rounds to give strength to our gate, we need to make sure the holes are perfectly aligned in each cross-piece. You should be able to get the dimensions from the sketchup file.
Measure from one side only. Mark it with pencil to remember.
Transfer measurements from the first cross piece to the others.
Don't forget about pencil width. Make notes to yourself ON THE WOOD about which side of a line to hit, etc.