Decide the type and style of Victorian garment you'd like to craft. Corsets, petticoats and bonnets were common for upper-class women; men of the same station wore frock coats, striped trousers and very full dress shirts. Lower class individuals donned much simpler and plainer clothing. The poor would rifle through secondhand stores and toil painstakingly to alter their clothes for a more respectable look.
Study the history of Victorian fashion and its most noteworthy figures. Look up information on Charles Worth, for instance, who established a Paris fashion house in 1858 and became one of the era's leading couturiers. Read descriptions of Victorian haute couture, which prized conspicuous style above all; delicate clothing during the era would be worn only twice, then discarded.
Shop for classic Victorian fabrics. Use white muslin, for example, to replicate an embroidered dress worn by a member of the famed Van Rensselaer family. Poplin, crinoline, lace and cashmere were other popular fabrics of the day.
Examine many Victorian fashion drawings and plates. These frequently come in the form of archival illustrations from the era's magazines and literature, such as "The Englishwoman's Domestic Magazine." Such sources are often the most authentic and detailed representation of Victorian style; they make an excellent base from which you can extract ideas.
Learn great skill in clothes-making techniques. Sewing, stitching, embroidering, hemming and accessorizing, among other techniques, all take place in a Herculean way when fashioning Victoria-era designs.