The first 24-48 hours after the injury is considered a critical treatment period and activities need to be curtailed. Gradually use the injured extremity as much as tolerated, by try to avoid any activities that cause pain. Often using a splint, sling, or crutches is necessary to adequately rest the injured body part.
For the first 48 hours post-injury, ice the sprain or strain 20 minutes at a time every 3-4 hours. The ice pack can be a bag of frozen vegetables (peas or corn), allowing you to be able to re-use the bag. Another popular treatment method is to fill paper cups with water then freeze the cup. Use the frozen cube like an ice cream cone, peeling away paper as the ice melts. Do NOT ice a sprain or strain for more than 20 minutes at a time!! You will not be helping heal the injury any faster, and you can cause damage to the tissues! Learn how to ice an injury here...
Use compression when elevating a sprain or strain in early treatment. Using an Ace bandage, wrap the area overlapping the elastic wrap by one-half of the width of the wrap. The wrap should be snug, but not cutting off circulation to the extremity. So, if your fingers or toes become cold, blue, or tingle, re-wrap!
Keep your sprain or strain as best possible--try to get it higher than your heart if possible. Elevate at night by placing pillows under your arm or leg.