It's not that simple and though we want to help, getting a booklet on spring making is in order. Anyone making springs shoud already be very familaiar with hardening and tempering steel.
Brief instructions, not enough info to keep you from failing:
All shaping (if you intend to forge or hammer a teper in the spring stock) and bending should be done while hot, in the incredibly bright red to orange range.
Then it should be polished to final finish carefully. No file marks are allowed across the spring but lengthwise is OK.
Then you heat till it does not allow a magnet to stick at all and quench. Since we do not know what steel you have, we can't tell you what is the best quench. Try transmission fluid first and plunge it in, red hot, and swirl around till it is cool. Take it out, clean it, and try to file it. If a new file skitters and does not cut it, the piece is hard. If it is not hard, then you have to reheat, possibly to a higher temp, and try different quenching medium. Water cools very fast and will harden springs very hard but can cause microscopic cracks that cause the spring to fail, IF it is very high carbon.
Assuming the spring is now hard, you need to temper it. There are many recipes for tempering. Do not trust your ability to simply heat it to the right color and get a good spring. Melt some lead till it is just melted and keep it that way, not as hot as hades. Soot up your hard spring in a candle and push it into the lead using a wire. Keep it in there for 10-15 minutes. Take it out and let it cool on its own. Clean it up and compress it way beyond what it will need to compress in the gun. If it does not go "Ping!" and does not bend, you have made a spring.