Wedding "disasters" come in many forms - from problems that are "fixable" such as the wrong flower in your bouquet, lipstick on your wedding gown, or the dj playing the wrong song for the first dance, to the necessity of major re-vamping of the day itself because of rain storms, blizzards and power outages, or the sudden illness of a member of the wedding party or a parent. No, deciding now to elope is probably NOT the best solution. However, there are some things that you can do to keep the stress levels down, and help avoid a traumatic meltdown should something not go as planned.
Bring ahead. Are you allowed to bring ceremony items during the rehearsal and leave them overnight? If so, bring your gown, shoes and accessories (have your bridesmaids do so as well). Box up your guest book, pen, unity candle and other ceremony accessories, and bring them to the rehearsal as well. You will be less likely to forget anything by calmly putting things together, rather than trying to grab everything on Saturday morning and rush out the door so you can be on time.
Have "quick fix" tools on hand. Have a wedding day emergency kit available. You'll want to include a basic sewing kit, tape, glue, aspirin, band-aids, spot cleaner (in case of spilled wine or wayward lipstick), nail file and make up for touch-ups
Have realistic expectations for your wedding day. Be aware of what can potentially happen. Keep things in perspective. And have a sense of humor. Some things are inevitable. A wedding cake at an outdoor reception will attract bugs. Others things may be upsetting at the time, but in reality not the end of the world - the periwinkle ribbon that you wanted in your bouquet looks too lavender, the vegetable medley is served instead of the green bean almondine. You're still getting married to the love of your life, so when you look back on this in one, five, or ten years will it really be that bad?
Extreme cases. Sadly, there are some disasters that cannot be foreseen, such as the sudden blizzard or rain storm that literally washes away all possibility of "planned perfection." Instead, in these types of extreme cases, the only thing to do is to go with the flow. Depending on how extreme the weather is, airports may be closed, and counties may be on a "Level 3 - Drive Only in an Emergency," alert, and many of your guests won't be able to make it. Power may be out, so electricity is non-existent. Without electric, your caterer and musicians/dj won't be able to provide their services. It won't be the wedding of your dreams, nor the one you've just spent many months planning, but when you wake up tomorrow, you'll be just as married to the love of your life. And when all is said and done, isn't that what it's all about?