Learning japanese. katakana, hiragana, romaji and kanji?

Question:

i'm definitely leaving kanji till last as it's hard and time consuming.
katakana, romaji or hiragana first? which is easier? which is more commonly used in japanese writing?
thanks

Answer:

People (Japanese kids, foreigners) begin with hiragana and katakana.
kanakana is used for those words coming from foreign words.
e.g. 1. ドア --> door, 2. カルタ --> carta (Portuguese), 3. キオスク --> киоск (= kiosk --> Russian)
romaji is phonetic notation for these (both hiragana and katakana) using LATIN alphabet, and we rarely use them in our writing actually.
e.g. 1. doa 2. karuta 3. kiosuku