If you think you have an easier time with pictures than just text, you could look at this thread:
@AmandaBear has drawn the mnemonics for all radicals and kanji of levels 1-4. You can also install the userscript linked in that thread to have the pictures integrated into the WaniKani site.
After level 4, you would still have to switch to the written mnemonics, but maybe at that point your brain has already gotten used to the mnemonics?