How to memorize hiragana fast (and actually keep it)
Short answer: Learn about 5 new hiragana a day, test yourself instead of rereading, check both directions (あ → a and a → あ), write each one by hand, and review on a spaced schedule. The 46 basic characters take about 10 days to meet once and a few weeks to become automatic.
1. Small daily sets beat one long session
Trying all 46 in a weekend feels fast, but most of them are gone a week later. Five new characters a day, plus a short review, is slower on day one and much faster by week three.
2. Test, don't reread
Looking at a chart feels like studying. Recalling the sound before you see the answer is what builds memory. Use a quiz, flashcards or cover the romaji with your hand.
3. Go both directions and listen
Reading あ as "a" is one skill; picking あ when you hear "a" is another. Practise kana to sound, sound to kana, and listening.
4. Write each character
Tracing a character a few times helps you notice the small differences, such as さ and ち, or ぬ and め.
5. Use spaced review
Review a character again just before you would forget it: after a day, then a few days, then a week. Characters you miss should come back sooner. This is the idea behind the Leitner box system.
6. Then add dakuten and combinations
Once the basic 46 are solid, the voiced marks (か → が) and small ゃゅょ combinations (きゃ, しゅ) are quick, because they reuse what you already know.
In Kanaday
Today's set gives you 5 new kana plus the ones due for review, a 10-question quiz in three directions, a trace pad on every card and 5-step spaced review. Every character is unlocked.