Taking the World History and US History Subject SAT Tests... HELP

I plan on taking the World History and US History Subject SAT tests this June 2nd and I am very nervous.
I am currently taking APUSH I my sophomore year and so far we have only learned up to the Gilded Age (our APUSH course is split up into two school years at our school because they feel as though they cannot teach everything thoroughly in one year) and I took Honors World History my freshman year in which we only got up to World War I.
This is definitely not enough for me to get an 800 on the test so what are some of your recommendations to help me cram for these two tests? Should I watch crash course videos? I also purchased Barron’s for both APUSH and AP World History in preparation for the two SAT Subject tests, would that be helpful as well or useless? Which parts of history do the SAT Subject test typically place the most emphasis on?
Thank you so much guys! Happy AP exam season as well.