What are the recommended techniques for optimizing Magento's XML sitemap submission?

@vinnie 

1. Prioritize important URLs: Determine which pages are most important for search engine indexing and prioritize them in the XML sitemap.
2. Keep it up-to-date: Keep the XML sitemap up-to-date by including newly added pages and removing outdated content.
3. Split the sitemap: When there are too many URLs, it is best to split the XML sitemap into smaller parts to avoid errors and improve crawlability.
4. Include metadata: Include important metadata such as the last modification date and the priority of each URL, as this helps search engines understand your site's structure.
5. Submit to Google and Bing: Submit the XML sitemap to Google and Bing using their respective search console tools to ensure proper indexing.
6. Use canonical tags: Make sure the URLs listed in the XML sitemap match the canonical URLs to avoid duplicate content.
7. Reduce crawl errors: Fix any errors such as broken links or duplicate content to improve the crawlability of your site and your XML sitemap.
8. Use a sitemap generator: Use a sitemap generator tool to automatically create and update your XML sitemap for optimal performance.