As a handworked adornment in vestments and altars within religious rites, lace has an extremely ancient history. In dreams, therefore, it comes to symbolize worship and perhaps the capturing of Spirit in craft of knotting. When joining two pieces of material such as linen, it signifies the transition between the physical and the spiritual realms.
Psychological / Emotional Perspective:
Much symbolism can be worked into lace, so it is useful to note what, if anything, is depicted pictorially in this manner in dreams. Altar cloths, for instance, might contain Christian images such as the cross or fertility symbols might be included in Wiccan robes. As a creative art, which is less practised nowadays, lace may alert us to our own creativity.
Everyday Material Aspects:
As a pastime, which kept women usefully employed and indeed was often the only source of income, from a practical perspective lace signifies gainful employment. More mundanely, to be tying our shoelaces suggests careful preparation. To be untying them suggests relaxation and informality. To lose shoelaces suggests insecurity.
Also consult the entries for Linen and Shoes.