First decide on your budget. Give yourself a range of price say $2,000 to $4,000. What ever (its your wedding) Now decide on where you are going to have the ceremony. This can have a cost to it and you don't want to find out to late that it takes you over your budget. Also this will let you know how many people it will hold. Don't want to invite 100 people and it only holds 50
Now make your lists of who you want to invite. I would suggest making 3 lists. All of the people you want to invite. Then those that you really would like to have there and finally those that absolutely must be there. Do this early as if you are going to have a dinner, reception, any type of party before or after, you will need these prices as it will make a difference which list you use. It is so much easier to do this early then have to go back to those that you might have said you would invite and now find that they just won't fit into the budget.
Now that you have your guests its time to look for your invitations. Use the internet here, you can find lots of places that can do this at a affordable price.
After you have your number of people you can now look at the prices for the food you are planning on having, or if you are going to have a bar, will it be open or a cash bar. Your cake is another expense, so shop around you can find prices that fit your budget. Don't forget cupcakes, this also works. You could make these your self, freeze and ice the day before of day of. You can find lots of things that you can decorate them with. Remember this is your wedding and your budget. You don't have to go crazy overboard.
Wedding dress, shop around and don't forget the internet here. You can also check out 2nd hand shops. Remember you only wear it once. There are also places that you can rent wedding dresses and bridesmaids dresses.
If you want to have favors there are lots of websites that can show you how to make them or where you can purchase at a reasonable price. Again Google if your friend here use it.
You can also just have a simple ceremony and then spend your money of a fun party or your honeym0on.
If you are using a wedding officiant, be sure to book them early, you don't want to have to search around to find someone to do the ceremony. I hope that it is me, but don't forget this step.
Congratulations on your upcoming wedding and have a Wonderful Wedding Day.