A number of stitchers said they laminate their charts before they begin stitching. Laminating will stiffen the paper chart and make it more durable. If a chart is folded so there's a crease where there are symbols, over time and with use, it will become difficult to read those symbols. Laminating over the fold will aid in preventing the symbols from disappearing. There's another advantage to using this method of keeping charts legible and intact.
Many stitchers like to mark on their charts.
There was some concern, however, about marking charts. Several stitchers wondered whether the markings themselves have the potential to rub off on the fabric on which one is stitching. One is that different kinds of markers will have more of a tendency to transfer to fabric than will others. I would also say it would be wise to make an effort to keep a marked chart from touching your stitching fabric at all. Several of the stitchers have floor stands complete with chart holders.