To do data augmentation, you can use the augment interface.
In the DATA section of your configuration file, you specify the name of the output list of files like so

[DATA]
augment = my_augmentations.csv

and then call the interface:

python - nkululeko.augment --config myconfig.ini

Once you augmentations have been processed, you can add them to the training in a new experiment:

[DATA]
databases = ['original data', 'augment']
augment = my_augmentations.csv
augment.type = csv
augment.absolute_path = False
augment.split_strategy = train