Alignment commands
bwa index -p hg19bwaidx -a bwtsw wg.fa
bwa aln -t 4 hg19bwaidx s_3_sequence.txt.gz > s_3_sequence.txt.bwa
References
Website
http://bio-bwa.sourceforge.net/
Tutorial
http://icb.med.cornell.edu/wiki/index.php/Elementolab/BWA_tutorial