The phrase "if you opt to use" is correct and usable in written English.
You can use this phrase when you are offering a choice, or when you are suggesting that someone might choose to do something. Example: "If you opt to use public transportation, it will be much less expensive than renting a car."
If you opt to use 64 cores in Google's range of high-memory machine types, you'll also get access to 416GB of RAM.
If you opt to use it, you can forgo carrying around the Shuffle's dock and cables, because the ShuffleBud does all the same tasks even with its reduced size.
If you opt to use this feature you can specify (or not) the baby's gender and due date along with "who with," "location" and whatever "story" you wish to report or conjure up.
You will be receiving monthly billing statements if you opt to use the paid plans.
It is best to avoid strong oxidizing agents, but, if you opt to use them, test your carpet carefully.
If you opt to use a powder blush, first use a translucent powder to set your base and control shine.
You could also click the small Facebook icon right beside the login form if you opted to use your Facebook account as your login.
You don't need to use a cooking thermometer to test the jam, but if you do opt to use one, the temperature of the jam will need to reach approximately 220 degrees Fahrenheit (104.4 degrees Celsius).
If you do opt to use an agency, call a few and ask for price quotes.
And even if you do opt to use one of these kinds of bottles, remember that it's still important to keep them clean to minimize bacterial contamination (including washing them and letting them dry before using them again and again).
Fertilizers are not usually necessary to begin with when growing peanuts, but if you do opt to use a fertilizer, make sure that it does not contain large amounts of nitrogen.
