Doing paper missions set to highest rep would be the fast way to lvl again but id say you cant start this until around lvl 10, until then just do as many missions as you can or join a good team it wont take long to get to lvl 10,
Newspaper you can start from lvl5. Though not wise to run around as lvl5 in a map where most are lvl10-20 mobs.
I would say, finish the first 2 contacts (both give nice story bonus) and just hunt anything you see on your way to missions. Dont forget tutorial lvl, thats a free lvl 
Try to do 1 mayhem to get your temp fly power, makes you more movable in the other zones. Focus on easy newspaper missions (steal XX from mooks/stupidmobs - or a defeat). Dont worry that your pets die, specialy in low lvl range they are plain meatshield.
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ok thanks both of you and i tried a mayhem mission ones and gave up because it was to hard but i might try again thanks to both =)
I always go heroic untill i'm a bit stronger. Maybe in a little few cases i go for the 3rd difficulty (the middle one - vicious?), making the same ammount of mob-spawn, but just 1 lvl higher.
50)Sinergy X/(50)Mika.
(50)MaceX/(50)Encore
Sign the petition, dont let CoH go down! SIGN!
yeah well for double xp weekend i was on malicious but it was still rather easy so i notched it up to vicious and found that it was difficult because i could only heal one pet at a team and my insps were only cabs and a couple of accuracys
Carry a tray mostly of greens, you can drag drop these on the names of your henchies, it'll boost them no matter how far away they are!
Cane through the tutorial, first two contacts then hit the papers.
Team up. Leave a friendly and inviting message on your search and mark yourself with the green (looking for missions)
I can vouch for Devirian having teamed with him on CoH!
"Like War_Hero said, leave it as it is, it toughens up the softies." - Naz Nomad
Union Heroes
War Borg - Leader of The Paragon Knights
Union Villains
McCabe - Co-leader of The Rogue Knights
Defiant - Supreme Hero
Well imade a thugs/poison on saturday and now he's at L.18 but i was thinking about changing poison to dark because it takes for ever to get the whole of my henchmen healed, but it would meen that i would have to level him up again and without the double xp it could take ahwhile so could i get help with the easiest way to level as a mastermind and what to avoid in the dark. thanks in advance