Home made Vanilla Extract

We are planning on making our own homemade vanilla extract. What I
want to do is to be able to give some as gifts. What size bottle would
anyone recommend for gifts? The other question is if I would need to
seal, like with canning, such jars of extract once it is made, after 6
months, or what? Would this homemade extract be ok just sitting on
shelves or should it be refrigerated or what? Any suggestions would be
appreciated.