The best place to go to find the information you need for revision for this course is the DT GCSE Exam Theory home page on Firefly here:
https://warminsterschool.fireflycloud.net/design-technology/gcse/gcse-exam-theory.
From this page you will find links to materials for each of the fifty chapters that make up the theory for the course. Every chapter has, as a minimum, a slideshow of theory content, a worksheet and an assessed homework sheet. You should have covered the vast majority of these throughout the course, so revisiting them will be good revision.
This link (www.educationumbrella.com/cloud/access/BWHNFK) should take you to an online version of the textbook which contains additional in chapter questions and end of section tests. Your teacher has access to the answers for these and will be willing to give you feedback if you want to submit work to them for assessment.
The book is also available to purchase on amazon at www.amazon.co.uk/AQA-GCSE-Design-Technology-8552/dp/1910523100/ref=sr_1_3?crid=3ODBK0OQDGQUG&dchild=1&keywords=aqa+gcse+design+and+technology+9-1&qid=1591173146&sprefix=aqa+gcse+des%2Caps%2C171&sr=8-3).
PG Online, the people who publish the textbook, have also prepared a ClearRevise book for the course. This is also available to purchase on amazon at https://www.amazon.co.uk/ClearRevise-GCSE-Design-Technology-8552/dp/1910523240/ref=sr_1_3?crid=HKNTW6OBN3KF&dchild=1&keywords=aqa+gcse+design+and+technology+pg+online&qid=1591193426&sprefix=aqa+gcse+de%2Caps%2C213&sr=8-3
Some other useful links for you:
Technology Student - a website written by a DT teacher and regularly updated to include current information and exam preparation material: www.technologystudent.com
Seneca Learning - AQA GCSE DT specific page: https://app.senecalearning.com/classroom/course/b4e64de8-a5d1-411b-81e2-aa4e2016e908/section/32cf34cb-5489-4210-9c3c-c504c87aadf7/session/start
BBC Bitesize DT specific page: https://www.bbc.co.uk/bitesize/subjects/zvg4d2p
Maths for DT resources: https://warminsterschool.fireflycloud.net/design-technology/maths-for-dt
Reading list:
In addition to the sources above, here is a list of books that might help develop your Design and Technology knowledge and understanding. Where possible I have included the amazon link in case you wish to purchase the book.
What is Design today? by George H. Marcus
Against the Odds by James Dyson
What makes great design by Susie Hodge
Stuff Matters by Mark Miodownik
The Design of Everyday Things by Don Norman
Exactly by Simon Winchester
There are many more books highlighted in the School's library. These can be found at the following link: https://warminsterschool.oliverasp.co.uk/library/home/search?search=%5B%22design%22%2C%22technology%22%5D&facets=%5B%5D&useListInput=false&isReloadFacets=false&searchField=KEYWORD&searchTerm=design%20technology&operator=bestMatch&available=false&includeNonPhysical=true&reviewedOnly=false&isAcceleratedReader=false&dataFile=false&sort=%7B%22field%22%3A%22relevanceRanking%22%2C%22direction%22%3A%22desc%22%2C%22label%22%3A%22Relevance%22%2C%22active%22%3Atrue%2C%22asc%22%3Afalse%7D&navigation=40&pageSize=20&listUuid=795ba560ac1f1f56306a12ee00105edb&origin=&facetGroupSize=%7B%22type%22%3A2%2C%22format%22%3A1%2C%22gmd%22%3A2%2C%22branch%22%3A1%2C%22publicationyear%22%3A36%2C%22resourcecollection%22%3A50%2C%22averageRating%22%3A3%2C%22author%22%3A50%2C%22series%22%3A50%2C%22subject%22%3A50%2C%22genre%22%3A2%2C%22publisher%22%3A50%2C%22corporateauthor%22%3A5%2C%22topiclist%22%3A7%7D
Exam practice is always beneficial when preparing for exams. The link below will take you to three different exam papers and their associated mark schemes. If you intend to sit the exam in September, We encourage you to go through these papers under exam conditions, before checking your answers against the mark schemes.