How about helium balloons? BALLOONS ALWAYS "MAKE" A CELEBRATION!
Ideally I chose to put a cluster of 3-5 on each table but if $ is tight you can always do every other table with 1 then 2 then 1 then 2 etc.....or 2 then 3 then 2 then 3 etc....depending on how much $ you want to spend. They are usually about $1 each.
You can weight them by tying the strings to a couple of heavy washers (that you get from a hardware store )and cover the washers with a pew type bow, if you know how to make them, or have someone who can do it for you. (Wide CRAFT ribbon is not expensive) The 2 tails of the bow can be cut long so they can extend down the table both ways a bit.....just to elongate the color of the bow.
Or , for an even cheaper, but pretty weight, you can take a sandwich baggie, fill it at least 1/2 way with salt, set the baggie in the center of a piece or 2 of tissue paper and gather the tissue up around it and tie it off to create a little package with the tissue points sticking up ...then tie your balloon ribbons to it. You could use crepe paper twists down the length of the tables with this...or not.
Also a small bag of those little glittery cut outs could be sprinkled down the center of each table to add a touch of whatever color you are accenting with. 1 bag goes quite a ways...some will end up on the floor though...but they sweep up easily, and usually you have to sweep after a party anyhow!
If you want candles on either side of your centerpiece you can buy those that are already in a small glass containers. They come in quite a variety of colors. Or buy tapers , if you have or can find glass candle holders.
Sometimes i have bought 2 different sizes of paper doilies, small for under each candle and larger for under the centerpiece....you can even add smaller bows to the base of your candles to match if you have used the pew bow in the center of the table.(A lot of these items can be bought from a dollar store)
Another thing that can add a touch of color and character, is to pick up some inexpensive silk flowers in the color of your choice, cut each flower , (or 2 or 3, depending on the size of them and what you think looks good,) loose from the cluster and tuck a few here and there beside or inside the bow (or at the base of the tissue pouch if you use that) and maybe a few at the base of your candles. They do not have to be glued in...they can simply be "placed" where you want them.
If you don`t like the little glittery cutouts idea to string along the center of the tables, but you have leftover silk flowers, you can cut the petals apart and sprinkle them along the center of the table.
If you want your flowers to glitter you can buy a can of spray glue and a small container of CLEAR glitter (Walmart will have these in the craft section) and simply spray each cluster of flowers lightly with the glue, THEN hold them over a paper bag, while they are still tacky, and sprinkle with the clear glitter and lightly shake the excess off into the bag....then stick the stems into a glass or vase until dry (the bag is so that you can reuse the glitter that falls off) Cut your flowers apart AFTER you have glittered them. Glittering bunches are easier and less messy that doing them individually....and you will want to do this outside if it`s warm enough, or in a garage with papers or an old shower curtian spread on the floor.
OPTIONAL: I have bought a cheap can of clear acrylic spray in the paint section of Walmarts too and used it as the glue for the glitter...and it works just fine too.
Whatever you do...be sure you have FUN doing it!