You can get a Historypin account using an existing Gmail account. There are both instructional videos and downloadable manuals available in their help section here. Instructions are clear and simple. Administrators also provide templates to generate spreadsheets of metadata for the bulk upload option. More instructions can be found here. Historypin has recommended formats, file size and minimum dimensions for images (i.e. jpg/png, under 10 MBs in size, minimum 600px on the longest side). Resolution can be flexible, as Historypin automatically re-sizes images to 600 x 400 px.