Congratulations on your first garden!!! Your best bet is to begin by designing and planting an area that you will see most often, either from your patio or from the kitchen window, dining area, etc. I suggest laying out a bed design using a supple garden hose or a rope--something you can see from inside the house. Create a border/bed with the rope and leave it in place a few days. Watch how the sun plays across it. See if you like it. If so, break ground, remove some sod, and see what kind of soil you have. You might want to have a soil test (a good idea) through the local county extension office. That way you'll know what to add to make great garden soil.
While that is going on, think about the plants you want. Check out the garden plans on bhg.com. There are plans for small yards, small beds, beds for butterflies, etc. I suggest making sure ot mix shrubs and perennials and annuals. Do a mix. Add a tree if you need some on your property.
Above all, start small with your garden efforts. A big garden will overwhelm you. Do a little this year, a little more next. I suggest trying to actually get a bed in this year simply because you'll be happy with something to dig into. Over the course of this year, begin to think about an overall plan for your yard. Do you want a vegetable area, flowers, bench, patio area, etc.? Figure this out and begin to lay it out. Bhg.com has tools to help you with this.
For birds, it's a good idea to have shrubs that offer shelter for nesting and roosting, as well as berries for food. Viburnums or hollies are nice for this.
Study the sun patterns in your yard, too, so you will know if you need sun or shade plants.
As you work on this year's little garden patch, you can begin dreaming about next year's and the years to come. Plan your trees and hardscape first and install that first. Then move to more planting beds.
Use containers to add color, too. Whatever you do, don't be overwhelmed. Just start small. Even if you later decide you don't want your first bed in the overall plan, that's okay. By then, you'll be more confident in gardening and have a new plan for that first garden bed.
Here are some great flowers for butterflies that are easy to grow:
butterfly bush (Buddleia, a shrub)
perennials: bee balm, coneflower, heliopsis, joe-pye weed, yarrow/achillea, butterfly weed (asclepias)
annuals: lantana, pentas, red salvia, blue salvia, zinnia
Above all, have fun!!