It's fun to think about the beautiful garden of your dreams but there is also the reality that you will be limited by some things such as time, location and weather. Try to be realistic about how much time you can spend planting, maintaining, weeding and harvesting. If you're limited by time one of the best things to do is limit the size of your garden. Buy transplants instead of starting from seed. To cut down on weeding mulch bare ground.
An idea of how much money you want to spend on your garden this upcoming year would be helpful. You're going to have one-time expenses to get going but use your imagination. Pots can be paper cups, plastic food containers, buckets, etc. Trellises can be old fences. I use the shelving from old pallet racks. You get the idea. Don't go crazy and buy more seeds/plants than you can take care of. Plant seeds instead of buying transplants when appropriate. I buy a couple of eggplants because I only want a few. You have to have the room and some equipment to start plants inside. I stink at growing peppers from seed. Some day I'll try again but this year I'll be buying.
The location is also a huge part of the success of your garden. Some plants like tomatoes need at least 8 hours of sun. Others can get by on 6 or less. If you don't have that much sun then use plants that need less sun such as leafy vegetables (lettuces, spinach, salad greens) and root vegetables. Leafy vegetables will be happier out of the hot summer sun. Peas will do well also.
You have to be able to water your garden easily. Make sure the garden hose can reach it. It's also handy to have your garden close enough to your house to dash out and pick a few veggies for dinner.
The soil has to have adequate drainage. You don't want your garden in a low, soggy area, If you want to plant on a gradual slope you may need to terrace it (build a low wall or border).
Fences can be very important to keep out those pesky cute animals that aren't so cute when they're destroying your hard work. Locating your garden near the house may help a little bit.
If none of this seems possible right now don't be discouraged. You'll be surprised how much can be grown in a few big pots. I know someone who used 5-gallon buckets for pots. He would move them so they could get sun. It also made it easy to mow the yard. He just picked them up and moved them!!