Hi John,
Your first step is to cut off the excess lace. All units come with extra lace that the customer trims off. Some people like to cut right up to the hair line. Others like to leave a row or two lace (it disappears when attached). And you also need to shampoo the unit. It looks curly at first and shampooing it will allow it to 'relax' and loosen up. Knot sealer is not required--it's a personal choice. Most hair wearers don't use knot sealer. Although it does help control shedding somewhat the downside is that the knot sealer is acrylic and makes the base a little stiffer. Also, the knots need to 'turn' in the direction of the hair styling so if you do decide to seal the knots it's a good idea to do it after the unit has been shampooed a few times and has 'settled in' to the way you style your hair.
Regards,
John