Live rock and sand 1 inch to 4 inch deep will help alot.
Google fishless cycle methods.
If you wish to make it a reef good lighting is a must.
Good quality salt.
Basic key things to know.
Research everything before you add it to your tank.
Flow is mandatory a small powerhead Will do the trick. You don't want deadspots in the water.
With a Reef especially good things take time bad things happen quick.
Basic steps I'd take is..
Grab some aragonite sand rinse well in water and to tank to create a sandbed.
Fill the tank approx 2/3 - 3/4 of saltwater.
Mix before adding to the tank. A specific gravity of 1.024 use ro
water to mix your salt in.
Add powerhead / heater to tank.
Let sandstorm settle.
Add live rock.
Start fishless cycle method. Monitor ammonia nitrite and nitrate.
Once tank is cycled water change with new water. About 50%
Feel free to add a fish you've researched.
Diligently maintain your waterchanges 20% a week should do it.
I may have missed something here its 3am my time hopefully someone will chip in and help