How to put a gene under the control of a regulable promoter?
If you're expressing the gene in E. coli, then you're almost certain to be using a plasmid or other ectopic gene vector. There are a wide variety of plasmids available, with many different promoters. With a commercial plasmid, you're not adding in the promoter sequence, but the gene sequence. You pick the promoter you want and then clone your gene sequence into the plasmid's multiple cloning site, which is designed to lie downstream the promoter. 

There are a variety of tools to design and order plasmids. A common plasmid repository is addgene and my favorite tool for designing plasmids prior to ordering is APE. 

Design the plasmid with APE or another tool, to be sure that everything looks good, then you can order the appropriate plasmid vector and enzyme cut site-flanked gene sequence and go to town cloning.