W.C.
We had our daughter in a toddler bed at this age, so we kept another mattress under the bed already made up. When we trained, we put her underware and stopped diapers cold turkey. She had 1 accedent during the day and 2 or 3 accedents at night, we changed the matterss and the jammies when she wet and washed everything. The extra mattress made this easy in the middle of the night.
I think that letting her feel it helped. Now she wakes up and will go to the bathroom by herself and return to bed without waking us.
Oh, we got the extra mattress at a consignment store, so it was only $15 which is one pack of diapers.