Before you sign up for a new credit card or click “I agree” on the user agreement for a website, scan through the fine print — or, at the very least, hit Control+F — and search for the word “arbitration.”

What you’ll likely find is that, in most cases, the company requires you to resolve all conflicts through a binding dispute resolution process, rather than going to court. These clauses are particularly common among financial companies, online services providers like Netflix and Amazon, cellphone carriers, and cable providers.

Some companies provide the option to opt out of mandatory arbitration, however — if you move quickly after signing up. Over a quarter of the more than 400 credit card contracts analyzed by the Consumer Financial Protection Bureau included an opt-out provision.

And if you’re a Citi Cards customer, you may even have gotten a chance for a do-over. Over the past year, the issuer revised its customer agreements, and has been contacting clients about the changes — and giving them a new opportunity to opt out of the company’s standard arbitration agreement.

But again, the time window is limited. Here’s an example of a letter sent recently to a MONEY staffer:

You have the right to reject this arbitration provision. If you reject, your account will no longer be subject to an arbitration provision. You can reject arbitration by writing to us at PO Box 6195, Sioux Falls, SD, 57117-6195 stating that you would like to reject the arbitration provision. Your letter must be postmarked on or before 12/22/2016. We will not close your account if you reject this change.

A Citi spokeswoman says the company expects to complete the mailings by early next year, and defends the use of arbitration as “an impartial, cost effective and timely method to resolve disputes.”

As with many opt-out notices, Citi’s instructions are vague. Companies often have their own specific method for having the consumer opt out of arbitration, says Amanda Werner, arbitration campaign manager for Americans for Financial Reform & Public Citizen. “Each clause has its own weird remedy or path for opting out,” she says. “And it’s not consistent for consumers … it’s not a one-size-fits-all,” she adds.

Werner and lawyers familiar with arbitration practices suggest you use the following guidelines when writing an opt-out letter.

Follow instructions: “It is important to read the opt-out provision carefully and to follow its instructions to the letter,” says Danielle Fuschetti, an attorney with California-based Sanford Heisler Kimpel. “And it’s always necessary to include enough information to identify the person and to indicate their intention to opt out.”

“It is important to read the opt-out provision carefully and to follow its instructions to the letter,” says Danielle Fuschetti, an attorney with California-based Sanford Heisler Kimpel. “And it’s always necessary to include enough information to identify the person and to indicate their intention to opt out.” Identify yourself: If the directions are vague, fall back on the typical business letter format, with date and addressee at the top. Include pertinent details like your account number, a customer ID if applicable and your contact information. As an example, you can use a form letter that New York law firm Davis & Gilbert drafted for eBay customers; it’s available as a download on Public Citizen’s website.

If the directions are vague, fall back on the typical business letter format, with date and addressee at the top. Include pertinent details like your account number, a customer ID if applicable and your contact information. As an example, you can use a form letter that New York law firm Davis & Gilbert drafted for eBay customers; it’s available as a download on Public Citizen’s website. Be direct: Skip any flowery language and be as clear as possible, Werner says. If you do go to court, the lawyers for the company will try to argue that you weren’t clear or didn’t mean what you said. “The fewer words you use, and the more direct and to-the-point you are, the more chance you have of being successful,” she says.

Skip any flowery language and be as clear as possible, Werner says. If you do go to court, the lawyers for the company will try to argue that you weren’t clear or didn’t mean what you said. “The fewer words you use, and the more direct and to-the-point you are, the more chance you have of being successful,” she says. Keep records: In general, the onus of proving you’ve successfully opted out of an arbitration provision is on you. If an email option is given, use that, says Werner — because an email automatically generates a time stamp. If you do need to send a physical letter, keep a copy for your records; if you send the letter via certified mail, you’ll get confirmation of its receipt. Save any response you get. And if you don’t hear back, follow up with customer service to ensure they received the opt-out notice.

In general, the onus of proving you’ve successfully opted out of an arbitration provision is on you. If an email option is given, use that, says Werner — because an email automatically generates a time stamp. If you do need to send a physical letter, keep a copy for your records; if you send the letter via certified mail, you’ll get confirmation of its receipt. Save any response you get. And if you don’t hear back, follow up with customer service to ensure they received the opt-out notice. Do it yourself: Despite the hassles, you should do this on your own, rather than hiring an attorney. If you were to get into a conflict eventually, the amount at issue would probably be fairly small potatoes — and you’d end up paying more for an attorney now than you would recover in court.

A cautionary tale turns up on Mouseprint.com — a site dedicated to highlighting the fine print in advertising and consumer agreements. A commenter identified as Carol Blacher says that she’d followed Citi’s instructions and wrote a letter, but got two responses — one that said she was good to go, and another stating she was ineligible. Several calls to customer service later, she’s still unclear where she stands. “It is 6 weeks since the last request and am still waiting,” she writes.

But don’t let the hassles discourage you from opting out, Werner says: “They’re obviously making it this cumbersome process to discourage consumers from actually using it.”