After adding the text you intend to process, SpinnerChief lists some basic information about it, such as the number of words, sentences and paragraphs. The 'Select Synonyms' section allows you to choose the terms you want to use, while the 'Quick Sentence Rewriting' and 'Quick Paragraph Rewriting' features enable you to rephrase certain pieces of text.
Imo it is not possible for google to detect properly spun content, it is not worth computing power it requires. They can do this using ngrams for example, but it is uses a lot of queries. And for example article spinner I coded beats this algo, so google cant detect that the content is spun. Manual spinning is also good but it takes more than 30 minutes per article.