Don't worry your pretty little head about it. Also try to get descriptions in dialogue or reactions, instead of exposition.
Like above, try inserting descriptions during dialogue. Example: Character has blonde hair and blue eyes. "Where is she?" Sam muttered, nervously running his fingers through his blonde locks. "We're going to be late." Sam slumped against a wall and exhaled a long breath. He stared at the night sky listlessly when a familiar voice drifted into his ear. "Did you miss me?" "Mary!?" He exclaimed, his formerly dull eyes shimmering with a vivid blue glow. "You're here!"
Depends on who you're introducing. If you're introducing your Main Character, pad it out throughout the first chapter or two. Mention their hair colour due to another character commenting about them dying it, or them running their hand through it, or, even, never mentioning the colour at all, only bringing it up because they're doing something like putting it into a pony tail, or feeling grateful for having short hair that dries fast after getting out of a shower, or something. The important thing here is to not let your Main Character's Description get in the way of the introduction to the story itself. This first chapter is important to getting people reading the story you're introducing, and receiving a detailed description of the main character is going to delay that and put some people off reading it. If your introducing a secondary character, depending on how far you are into the story and the character's role, how you will want to introduce them varies wildly. Unimportant side characters (or seemingly unimportant side characters) may receive a two-word description of the uniform they're wearing, one of their articles of clothing, or some other notable characteristic of theirs. The crush of the MC or their best friend, however, may receive a detailed description of their hair length and colour, their dazzling smile and their build, spoken by the love-struck MC/Friend before said MC/Friend stops their gushing (or starts ignoring them, if the MC). In between that is introducing characters who appear to be important to the plot in the immediate future. Spaced out descriptions, like suggested for the MC, or Info Dumps, similar to what's suggested for the Crush, can both work for this, particularly if the individual in question is new to the MC. You just need to ensure that the introduction doesn't damage the pacing of the rest of the story.